Invisibility and you

[Dmdork]

So, I was on the raw thread with a question and got this prompt reply:


Quote Originally Posted by Dmdork View Post
Q457 if a creature is invisible and like 20feet away, can I walk up to it and attack it, albeit with disadvantage?
A457-Yes. Unless the invisible creature takes the Hide action and their Stealth score beats the Perception of the attacker.

This doesn't sit well with me. I hope one of you can help me to understand how this is plausible. It seems like invisibility doesn't give you so much. It's the same with blindness. Blindness/invisibility do not effect your movement rate. Why? I understand keeping it simple, but this seems unrealistic

[MaxWilson]

So, I was on the raw thread with a question and got this prompt reply:


Quote Originally Posted by Dmdork View Post
Q457 if a creature is invisible and like 20feet away, can I walk up to it and attack it, albeit with disadvantage?
A457-Yes. Unless the invisible creature takes the Hide action and their Stealth score beats the Perception of the attacker.

This doesn't sit well with me. I hope one of you can help me to understand how this is plausible. It seems like invisibility doesn't give you so much. It's the same with blindness. Blindness/invisibility do not effect your movement rate. Why? I understand keeping it simple, but this seems unrealistic

There is no written rule for not being able to find an invisible creature, or for blindness reducing your movement rate, because 5E expects the DM to identify and implement any such situational factors when they apply.

If you walk into a room and there's an invisible man standing in the corner, the DM is not obligated to tell you, "There's an invisible man in the corner." But if he does tell you (e.g. "You can hear an invisible man breathing in the corner"), then you can certainly walk up and stab him. And if you're stumbling along in the Underdark, the DM can tell you, "Okay, the ground you're walking over is really bumpy, and you can't see. If you move at full speed, you'll need to make a DC 10 Dexterity check every round to avoid tripping and falling, unless you light a torch."

In short, the answer you got from the RAW thread was wrong, or at the very least incomplete. The real answer is, "There are no rules for that. Ask your DM."

[IShouldntBehere]

The simplest way to resolve this is to not think of "Invisibility" as but more of Cloaking effect like the "Predator" effect or cloaked units in a video game like Starcraft.

You turn transparent in way kind of like you're made out of glass. You're much harder to see and if you do a good job of staying perfectly still, you'll go unnoticed. However when moving around or just generally not doing a good job being stealthy you have telltale shimmer/distortion effect, something an alert observer can pick up on and move towards even if they don't have an exact fix on ever part of your body.


There's also an interpretation that basically gives all humans hyper-sonar such that in a pitch black room everyone knows the exact location of everyone else who isn't actively sneaking around. No my bag, but hey to each their own.

[Cybren]

The important thing is to be hidden, you need to take the hide action, but just because someone didn't take the hide action doesn't mean they're noticed. This is one of those areas where the table should respect the fictional positioning. If someone is invisible and unconscious in a 200x200ft room, I'd say it's a bad DM call to let another character to walk in there and make an attack roll against them

[RSP]

If someone is invisible and waiting in a room for someone to enter, I'd assume the DM would grant them a Stealth roll to represent their hiding, if that's indeed what they're doing (i.e. waiting in ambush).

If however, it's just a Wizard who likes having Invisibilty up while knocking out some push ups, you're going to know roughly (within a 5 ft square) where s/he is based on the usual sounds associated with exercising.

It can be weird that blindness doesn't equal not knowing where people are and the blinded condition certainly leaves a lot open to interpretation, but that's why the game is designed with DM empowerment in mind.

[MaxWilson]

If someone is invisible and waiting in a room for someone to enter, I'd assume the DM would grant them a Stealth roll to represent their hiding, if that's indeed what they're doing (i.e. waiting in ambush).

If however, it's just a Wizard who likes having Invisibilty up while knocking out some push ups, you're going to know roughly (within a 5 ft square) where s/he is based on the usual sounds associated with exercising.

And if he's invisibly reading a book?

There are no rules for it, but there are no rules for setting Perception DCs for lots of things. It would be reasonable for a DM to require a DC 10 or DC 15 Perception check to realize that there is an invisible person sitting in that chair there reading.

I mean, come on! Humans beings can't even always spot a human being in a gorilla suit in plain view! Ref: https://www.youtube.com/watch?v=vJG698U2Mvo

[RSP]

Certainly a DM could rule that way, but the Invisibilty rules follow with the rest of 5e in that they keep it pretty simple, in the hopes that tables that want to make changes can do so easily, rather than start with a complex series of rules that require substantial changes to alter.

[MaxWilson]

Certainly a DM could rule that way, but the Invisibilty rules follow with the rest of 5e in that they keep it pretty simple, in the hopes that tables that want to make changes can do so easily, rather than start with a complex series of rules that require substantial changes to alter.

Precisely--there are no rules on this topic, so there is no RAW. The answer given in the RAW thread was wrong/incomplete/misleading, take your pick.

[RSP]

There certainly are RAW for invisibility; just because you don't agree with the RAW that the location of an invisible creature can be automatically noticed if it isn't also hiding, doesn't mean the rules don't exist.

[Ashrym]

There are rules. Invisibility enables hiding where there is no cover or concealment. That doesn't mean it allows for silence or prevents disturbance in the environment like seeing foot prints. If the invisible person is trying to hide that is normally handled against passive perception, which generally results in the invisible person being hidden or remaining hidden by default with the exception of perceptive characters, which makes sense.

Invisibility still doesn't provide visibility when the invisible person is detected. That's why attacking someone who is invisible is done so with disadvantage and why the invisible person can attack someone with advantage.

That's easily RAW.


Invisible
• An invisible creature is impossible to see without the aid of magic or a special sense. For the purpose of hiding, the creature is heavily obscured. The creature’s location can be detected by any noise it makes or any tracks it leaves.
• Attack rolls against the creature have disadvantage, and the creature’s attack rolls have advantage.

Sensing someone without actively looking for them gets back to passive perception. The invisible person has a hide roll and if that roll is higher than any passive perception then there's nothing noticed. If it's a tie, then the existing condition continues, which is the person is hidden and unseen.

That's one of the fun things with arcane tricksters; reliable talent and skill while using invisibility makes for some pretty easy stealth, but even a wizard with a +2 dex bonus and proficiency isn't noticed often. It seems to follow what I would expect from the spell given how hard it is not to leave footprints in grass or on a floor. Even the dirt from the bottom of the invisible person's boots will leave dust or dirt tracks on as the person steps away from them, so notice seems possible.

[MaxWilson]

There certainly are RAW for invisibility; just because you don't agree with the RAW that the location of an invisible creature can be automatically noticed if it isn't also hiding, doesn't mean the rules don't exist.

There is no such rule. There is no guarantee anywhere that a PC will automatically see a person or object that is not deliberately hidden.

The rule is that the DM decides. If necessary, he sets a Perception DC and asks for a check.


Perception. Your Wisdom (Perception) check lets you spot, hear, or otherwise detect the presence of something. It measures your general awareness of your surroundings and the keenness of your senses. For example, you might try to hear a conversation through a closed door, eavesdrop under an open window, or hear monsters moving stealthily in the forest. Or you might try to spot things that are obscured or easy to miss, whether they are orcs lying in ambush on a road, thugs hiding in the shadows of an alley, or candlelight under a closed secret door.

[Ashrym]

There is no such rule. There is no guarantee anywhere that a PC will automatically see a person or object that is not deliberately hidden.

The rule is that the DM decides. If necessary, he sets a Perception DC and asks for a check.

I just quoted the rules for you. Hiding or hiding an object is an opposed check and has clear rules for such. Even if it's noticing scuff marks on the floor or an area where dust is not settling because an invisible object is covering that part of the floor there can be signs. The invisible condition is clear on what it does.

If the person isn't hiding, then it's not hard to detect their presence by noise etc because they aren't trying to be quiet etc. They are not seen but they are detected because they are not trying to be undetected. If they are trying to be stealthy, they get their stealth check.

The PC will never see a person or object that is not deliberately hidden without some means to see invisibility. The invisible condition has already stated it's impossible to see the person or object. It's not seeing the person or object that's in question. It's noticing details to indicate the presence of the person or object, which has nothing to do with directly seeing the person or object.

[krugaan]

There should really be a sticky for invisibility+hide, minor conjuration, and minor illusion, so that the same ideas don't get rehashed over and over every month or so.

[RickAllison]

There should really be a sticky for invisibility+hide, minor conjuration, and minor illusion, so that the same ideas don't get rehashed over and over every month or so.

But then it would cut down on the thread-count so much! And I want this forum to breathe like Egyptian cotton...

What do you mean that higher thread-count doesn't make Internet forums softer?

[krugaan]

But then it would cut down on the thread-count so much! And I want this forum to breathe like Egyptian cotton...

What do you mean that higher thread-count doesn't make Internet forums softer?

Lol, I see whut you did thar.

[MaxWilson]

I just quoted the rules for you. Hiding or hiding an object is an opposed check and has clear rules for such. Even if it's noticing scuff marks on the floor or an area where dust is not settling because an invisible object is covering that part of the floor there can be signs. The invisible condition is clear on what it does.

Sigh. I just quoted the rules for you, and made it clear that deliberate hiding is NOT what we are being discussed--so your rules quote isn't even relevant. Unlike the rules I just quoted for you, which are wholly relevant to the invisible book-reading wizard.

Noticing easy-to-overlook stuff requires a Perception check even if it's not deliberately hidden. Ask your DM for details, because the PHB has no other rules on this subject except "ask your DM".

Again:


Perception. Your Wisdom (Perception) check lets you spot, hear, or otherwise detect the presence of something. It measures your general awareness of your surroundings and the keenness of your senses. For example, you might try to hear a conversation through a closed door, eavesdrop under an open window, or hear monsters moving stealthily in the forest. Or you might try to spot things that are obscured or easy to miss, whether they are orcs lying in ambush on a road, thugs hiding in the shadows of an alley, or candlelight under a closed secret door.

There is no rule anywhere that specifies that an invisible book-reading wizard is auto-detected. Of course there is no such rule--it's a DM judgment call, and likely to involve a Perception check, as specified in the rules text I just quoted.

[Ashrym]

Sigh. I just quoted the rules for you, and made it clear that deliberate hiding is NOT what we are being discussed--so your rules quote isn't even relevant. Unlike the rules I just quoted for you, which are wholly relevant to the invisible book-reading wizard.

Noticing easy-to-overlook stuff requires a Perception check even if it's not deliberately hidden. Ask your DM for details, because the PHB has no other rules on this subject except "ask your DM".

Again:



There is no rule anywhere that specifies that an invisible book-reading wizard is auto-detected. Of course there is no such rule--it's a DM judgment call, and likely to involve a Perception check, as specified in the rules text I just quoted.

You are ignoring passive perception to notice the invisible book-reading wizard. It's even an specific item on the character sheets. Passive checks exist because they are automatic and a rule to passively detect the presence of the wizard.


Such a check can represent the average result for a task done repeatedly, such as searching for secret doors over and over again, or can be used when the DM wants to secretly determine whether the characters succeed at something without rolling dice, such as noticing a hidden monster. Here’s how to determine a character’s total for a passive check:
10 + all modifiers that normally apply to the check
If the character has advantage on the check, add 5. For disadvantage, subtract 5. The game refers to a passive check total as a score. For example, if a 1st-level character has a Wisdom of 15 and proficiency in Perception, he or she has a passive Wisdom (Perception) score of 14. The rules on hiding in the “Dexterity” section below rely on passive checks, as do the exploration rules in chapter 8.

Perhaps you should sigh again. Clearly it's important to your ability to ignore the other two sets of rules I referenced. ;-)

For further reference from chapter 8:


Use the passive Wisdom (Perception) scores of the characters to determine whether anyone in the group notices a hidden threat.

Clearly there's a rule for auto-detecting the presence of that invisible book-reading wizard. What I previously quoted reinforces that the characters can notice the presence by even though they cannot see the actual wizard.

[Segev]

But then it would cut down on the thread-count so much! And I want this forum to breathe like Egyptian cotton...

We already know it can withstand flame wars of up to 10,000 degrees!

http://i142.photobucket.com/albums/r105/BramBook/Edna3.jpg

[Specter]

How I do it (feel free to disregard it):

When an invisible person does anything stealthy, I have them roll a stealth check (not as an action, that would be nonsensical). If they get a 20 or higher, the enemy can't know their position, except for a general direction (in front, behind, etc.). If they get from 11 to 19, I give people a 10-foot cube where the invisible creature is (so that AoE can affect it). If they take less than 10, everyone knows where they are.

[Segev]

Since the Invisibility condition treats those enjoying it as being Heavily Obscured, and Heavily Obscured regions cause viewers to be Blinded wrt anything in them, and Blinded creatures automatically fail any check which would require sight (all pulled from a quick perusal of conditions and environmental rules in the 5e SRD), then if you walk into a room where an invisible wizard leaning on a wall, people-watching, you will automatically fail to notice him unless he does something to let you use a sense other than sight.

If he's stinky, you can smell him. If he sneezes, talks, or makes noise by moving, you can hear him. If he kicks around dust or leaves footprints while pacing, you can see those. But as long as sight-of-him is the only way you can detect him, you automatically fail. Per the rules.

[Malifice]

I run in by RAW.

If you cast invsiblity in combat, your enemies know where you are sufficiently to be able to swing swords in your general direction like mad (attack with disadvantage). If you want to hide from them you can (thanks to invisibility) and need to make a Stealth check (as normal for hiding) as an action. Same deal if you want to sneak off (move silently, leaving no tracks or signs of your passage). I want a Stealth check via the Hide action.

Being invisible already makes you immune to Attacks of Opportunity, and most spells. It lets you hide at will (as an action), and grants you advantage on attack rolls and disadvantage on attacks coming back your way.

Those of you that want to drive it up to auto win at stealth checks, free Hide actions and more, are wrong.

Weirdly, youre often the same people that decry spellcasters as being too powerful.

If you want to get maximum value out of invisibilty, take 2 levels in Rogue. Otherwise be thankful for what it does and move on.

[hymer]

Since the Invisibility condition treats those enjoying it as being Heavily Obscured

But only 'for the purpose of hiding' according to my PHB. Plenty of room for weasels in both directions, depending on whether someone wants to say that 'hiding' means the action and game term, and not just a general description.

[MaxWilson]

You are ignoring passive perception to notice the invisible book-reading wizard. It's even an specific item on the character sheets. Passive checks exist because they are automatic and a rule to passively detect the presence of the wizard.

I'm not ignoring it--but you're missing the point. The DM sets the DC, and it doesn't necessarily have anything to do with Dexterity (Stealth), because there's no "hiding" involved.


Perhaps you should sigh again. Clearly it's important to your ability to ignore the other two sets of rules I referenced. ;-)

For further reference from chapter 8:

Clearly there's a rule for auto-detecting the presence of that invisible book-reading wizard. What I previously quoted reinforces that the characters can notice the presence by even though they cannot see the actual wizard.

Maybe that's the disconnect then. You keep quoting things that, to me, seem both obvious and irrelevant. It's not under dispute that the characters can notice the presence. But you keep defending the position (or at least disagreeing with me disagreeing) that a character who has not hidden is, "by RAW", automatically detected. The text doesn't support that position, and neither do any of the things you've quoted. The text does support the sentence I bolded ("characters can notice the presence"), but that point isn't under dispute.

Edit: also, we're apparently using "automatic" in different ways. When you say that passive checks are "automatic", you mean because they don't require a die roll or any action on the player's part. That's not really automatic though, because it's possible to fail. A Perception-18 Lore Bard may be able to detect that book-reading wizard without any action on the part of the player, but it's not automatic for PCs in general--the Lore Bard had to practice and practice to get where he is (Expertise).

[Ashrym]

Since the Invisibility condition treats those enjoying it as being Heavily Obscured, and Heavily Obscured regions cause viewers to be Blinded wrt anything in them, and Blinded creatures automatically fail any check which would require sight (all pulled from a quick perusal of conditions and environmental rules in the 5e SRD), then if you walk into a room where an invisible wizard leaning on a wall, people-watching, you will automatically fail to notice him unless he does something to let you use a sense other than sight.

If he's stinky, you can smell him. If he sneezes, talks, or makes noise by moving, you can hear him. If he kicks around dust or leaves footprints while pacing, you can see those. But as long as sight-of-him is the only way you can detect him, you automatically fail. Per the rules.

This is specific to the invisible condition.

"The creature’s location can be detected by any noise it makes or any tracks it leaves. "

Specific beats general.

Your quote is being misapplied. The party will automatically fail to see him, correct; they will not automatically fail to hear or smell him, or fail to see visible signs of his presence such as the footprints that were specifically mentioned. In no case is the party detecting the invisible person by visual means because it's impossible to see the invisible person by visible means as per the description of the invisibility description, thus completely invalidating your whole argument because it's not a sight based check and never was. ;)

[Ashrym]

I'm not ignoring it--but you're missing the point. The DM sets the DC, and it doesn't necessarily have anything to do with Dexterity (Stealth), because there's no "hiding" involved.



Maybe that's the disconnect then. You keep quoting things that, to me, seem both obvious and irrelevant. It's not under dispute that the characters can notice the presence. But you keep defending the position (or at least disagreeing with me disagreeing) that a character who has not hidden is, "by RAW", automatically detected. The text doesn't support that position, and neither do any of the things you've quoted. The text does support the sentence I bolded ("characters can notice the presence"), but that point isn't under dispute.

It's an opposed check, not a static DC. Look up opposed checks. What the DM does is explain to the party what they see, hear, feel, smell, etc. What you are describing is a forest bereft of sound because there are trees in the way. Players automatically hear and smell things just like they automatically see things with no checks required, just as much as they breath and take a crap without requiring checks.

All you are doing is ignoring the environment that they would detect and the clear mechanics on how they would detect it. If an invisible person isn't trying to be quiet then why would they not be heard normally. If they are being quiet then they get their stealth check because they are attempting to be stealthy. Following your reasoning, a person who is not trying to hide by being invisible has a better chance of doing it than a person trying to hide because in not trying to hide you are not giving the perception check per chapter 8's clear rules, but if they hide then there's suddenly an opposed check.

It's not that I am missing the point. It's that your point is off base and selectively chosen so as to ignore the actual rules that are relevant to the situation. Presumably to make invisibility more powerful than it is for whatever reason.

[MaxWilson]

Your quote is being misapplied. The party will automatically fail to see him, correct; they will not automatically fail to hear or smell him, or fail to see visible signs of his presence such as the footprints that were specifically mentioned. In no case is the party detecting the invisible person by visual means because it's impossible to see the invisible person by visible means as per the description of the invisibility description, thus completely invalidating your whole argument because it's not a sight based check and never was. ;)

Are you arguing that:

(1) The party will not necessarily automatically fail to see him; or
(2) The party will automatically not-fail to see him?

In your view, is the chance of them detecting him 100%?


All you are doing is ignoring the environment that they would detect and the clear mechanics on how they would detect it. If an invisible person isn't trying to be quiet then why would they not be heard normally. If they are being quiet then they get their stealth check because they are attempting to be stealthy.

This is wrong-headed. You know why we are talking about people-watching and book-reading in this thread? That's right, because they are both activities which are done quietly despite lacking any intention of being stealthy. If you literally cannot conceive of anyone being quiet without an intention of being sneaky, that's a failure of imagination.


Players automatically hear and smell things just like they automatically see things with no checks required, just as much as they breath... without requiring checks.

No they don't.

I've already quoted to you the rules that demonstrate that you can fail to notice things that aren't being stealthy. Moreover, if you've played D&D for more than twenty minutes in your life, you're probably well aware that some things require a certain level of Perception to notice without examination. A quick perusal of WotC's recent adventures will reveal a plethora of Perception checks, each of which yields extra information when passed. PCs do not "automatically" hear and smell and see everything around them "with no checks required."

I think we're done here.

[Cybren]

Unconscious creatures can't take actions. Ruling that only creatures that take the hide action can escape notice while invisible means that you would notice an unconscious invisible creature from 100 feet away and could make attack rolls with a crossbow with only disadvantage as your penalty.

Just because a creature can be noticed does not mean it is, whether they're trying to escape notice or not. Passive perception doesn't help in this case, because there's no such thing as a passive stealth value to compare it to.

[Dalebert]

It seems like invisibility doesn't give you so much.

*exaggerated jaw-dropping expression*
It gives you advantage against enemies.
It imposes disadvantage on your enemies vs you.
It makes you impossible to target with MANY spells. IMPOSSIBLE.
It allows you to hide without a hiding place.


I understand keeping it simple, but this seems unrealistic

Can we please think about balance. Screw realism. Screw realism really hard with a rusty phillips head screwdriver. Realism complicates the game and often breaks the balance of the game. Invisibility is a perfect example.


The simplest way to resolve this is to not think of "Invisibility" as but more of Cloaking effect like the "Predator" effect or cloaked units in a video game like Starcraft.

I like that. I might use that. It achieves a degree of satisfying realism while maintaining balance and not over-complicating the mechanics and math.


Those of you that want to drive it up to auto win at stealth checks, free Hide actions and more, are wrong.

I agree with your judgment on invisibility but I won't go so far as to declare anyone "wrong". The fact that people argue this much means there is some room for interpretation. That said, if I were playing a rogue in a game with a DM who interprets invisibility SO powerfully for just a 2nd level spell, I would feel royally nerfed. Cunning action is the defining aspect of a rogue and if you give a huge chunk of that to everyone, I'd be pretty ticked off. Actions only matter in combat but in combat they matter a lot. If you want to stay completely undetected enough to avoid attacks completely while invisible during combat, you should have to blow your action for it. It's a simple matter of balance and being fair to rogues and not making invisibility obscenely powerful.

[Malifice]

It's an opposed check, not a static DC. Look up opposed checks. What the DM does is explain to the party what they see, hear, feel, smell, etc. What you are describing is a forest bereft of sound because there are trees in the way. Players automatically hear and smell things just like they automatically see things with no checks required, just as much as they breath and take a crap without requiring checks.

All you are doing is ignoring the environment that they would detect and the clear mechanics on how they would detect it. If an invisible person isn't trying to be quiet then why would they not be heard normally. If they are being quiet then they get their stealth check because they are attempting to be stealthy. Following your reasoning, a person who is not trying to hide by being invisible has a better chance of doing it than a person trying to hide because in not trying to hide you are not giving the perception check per chapter 8's clear rules, but if they hide then there's suddenly an opposed check.

It's not that I am missing the point. It's that your point is off base and selectively chosen so as to ignore the actual rules that are relevant to the situation. Presumably to make invisibility more powerful than it is for whatever reason.

You're 100 percent correct and youre also banging your head against a brick wall. Ive had this same argument a billion times.

To be fair, its a lot less heated after a while. I think most people have settled on the (you still need to make a stealth check via the Hide action if you want to be undetectable in most situations barring outliers) interpretation.

For the love of God dont bring Halflings or Wood elves into the discussion. Then we get into Jack in the Box rogues and all sorts of hillarity and rage ensues.

[Ashrym]

Are you arguing that:

(1) The party will not necessarily automatically fail to see him; or
(2) The party will automatically not-fail to see him?

In your view, is the chance of them detecting him 100%?

I can only quote that it is impossible for the party to see him in response to item 1 so many times. The party cannot see him unless they can see invisibility somehow. They cannot see him. Item 2 is closer because unless the person reading the book is holding his breath, not occasionally shifting his weight to be comfortable, etc he's making some quiet noise at least. Unless he has tried to cover up his smell somehow there are odors there. Unless he's also levitating or something (which he's not because of concentration competition) then he's leaving tracks or footprints, or a butt indentation in the sofa, or something.

If he's not trying to hide his presence then the party will automatically detect his presence just like going into any other place where someone is flipping pages in a musty old tomb and not holding his breath. That's no different than noticing someone in a fog cloud or a dark room except the visible signs of his presence are not also hidden in concealment like a fog cloud or dark room.

In my view, if he's not trying to be undetected then the chance of detecting him would be 100%. In my view, since he's gone to the effort of being invisible then he's likely trying to be undetected, otherwise what was the point of being invisible? Also, in my view, since he's trying to be undetected there are standard rules where he hides using invisiblity for concealment that require a stealth check and unless the party is actively looking for them (which requires active rolls) then his stealth check is measured against their passive perceptions, tie going to him due to the previous state rule on ties.

In the end, if he's not actually trying to hide there's no reason that a person would not notice his presence automatically because the invisibility status says they don't see him but they do hear him and see his tracks. It's the invisibility status that you are using in your example. He's doing a quiet activity but not a silent activity; that would require not moving, holding his breath or at least attempting to control the sound of his breathing, and stopping leafing through pages.

There's no rule stating players fail to detect those other things when someone is invisible. There is a definite rule that the players hear the invisible person and see his or here tracks in the invisible status effect that doesn't require a roll or check per the statement (you're adding that generalization instead of following the specific effect statements there). There are definite rules to opposed checks if a person is trying to use concealment for stealth.

I don't mean to be repetitive, but selectively choosing and ignoring rules, especially ones specifically in print pertaining to your example, does not mean there are no rules. Don't you find it odd that you are using invisibility in your example and you told me the rule I quoted on invisibility isn't the one to use?


This is wrong-headed. You know why we are talking about people-watching and book-reading in this thread? That's right, because they are both activities which are done quietly despite lacking any intention of being stealthy. If you literally cannot conceive of anyone being quiet without an intention of being sneaky, that's a failure of imagination.

I can. Quiet and quiet beyond notice are two different things. This wasn't question of imagination regardless; you had claimed there weren't RAW rules and that clearly isn't the case. You're argument works both ways regardless. You don't have the imagination to present what the players do see and hear and smell regardless of what they don't; it's a definitive part of the invisibility effect. ;)



No they don't.

Yes, they do. There's no check to hear noises that would normally be heard. They are just heard. There is no check to see if a person knows he's wet in the rain just because he cannot see through his clothes. A character's senses are always on. Invisibility doesn't shut that off. There's an option to make it hard to hear and add a check at the DM's discretion, yes, but the wizard in question trying to be hard to hear is still an opposed check in the rules that you are ignoring, and passive perception is always on. That's why the rules specifically state to use it in chapter 8 and match up with the invisibility description to demonstrate what a person would or wouldn't notice with that passive perception check.

All you are doing is using blinders to ignore rules that don't match how you want the situation with invisibility to play out. You claimed there was nothing RAW but RAW is plain and clear. It didn't stop existing just because you were being selective in applying rules.


I've already quoted to you the rules that demonstrate that you can fail to notice things that aren't being stealthy. Moreover, if you've played D&D for more than twenty minutes in your life, you're probably well aware that some things require a certain level of Perception to notice without examination. A quick perusal of WotC's recent adventures will reveal a plethora of Perception checks, each of which yields extra information when passed. PCs do not "automatically" hear and smell and see everything around them "with no checks required."

You did quote them. Those were the selective general rules that didn't change the rules specific to the situation (invisibility and passive perception) that I also quoted to refute your rules, and also ignored the general rule were the DM describes what the players do see or hear or smell in there environment; which would be described based on the invisibility and passive perception rules presented.

Passive perception is on. That's why it exists. It's the ability used when there's a hidden threat, like an invisible wizard. It's also not required to based solely on sight as per the description of perception.

I'll add more for you, again from the PHB.


Your Wisdom (Perception) check lets you spot, hear, or otherwise detect the presence of something.... Or you might try to spot things that are obscured or easy to miss

Even if you exercise the DM prerogative to say the invisible wizard is exceptionally quiet the passive perception is still going to be there for players to observe that which would normally be easy to miss. That's not a question of lack or rules or imagination. That the principle of heroes being exceptional in the first place.


I think we're done here.

If you think so then I'm fine with dropping it. I was pointing you to the rules you claimed did not exist, which they obviously do.

[RSP]

Invisibilty and hiding in combat, is different than Invisibility and hiding outside of combat.

Per RAW:

In combat characters are assumed to be aware of their surroundings and it takes an action to hide.

Out of combat, actions matter less because their is no action economy.

Per the Hiding rules:

The DM decides when circumstances are appropriate for hiding.

Now, as hiding is stated as an action during combat, the basic idea is that whether or not one uses invisibility, they aren't hidden unless they take the hide action and win a contested stealth v perception roll.

Outside of combat, a DM could very well decide that the circumstance for hiding has been met in the case of the invisible wizard reading a book. In that case, the wizard would make a stealth check and it would be opposed by the passive perception of anyone entering the room (or a roll of those entering were actively trying to look for hidden items/creatures).

Me personally, I see it as taking the hide action if a person is invisible and "does nothing (i.e. The invisible wizard leaning against the wall observing)." That is, opting not to take an action and opting not to move, would default to the hide action. But that's just my way to play it.

[Ashrym]

Unconscious creatures can't take actions. Ruling that only creatures that take the hide action can escape notice while invisible means that you would notice an unconscious invisible creature from 100 feet away and could make attack rolls with a crossbow with only disadvantage as your penalty.

Just because a creature can be noticed does not mean it is, whether they're trying to escape notice or not. Passive perception doesn't help in this case, because there's no such thing as a passive stealth value to compare it to.

Considering the body sized impression in the dirt and the sound of snoring, I'm thinking there's something. As proven, perception isn't just sight and the area around the invisible person isn't also invisible.

[Cybren]

Considering the body sized impression in the dirt and the sound of snoring, I'm thinking there's something. As proven, perception isn't just sight and the area around the invisible person isn't also invisible.
Why is there suddenly dirt?

[Ashrym]

Why is there suddenly dirt?

It doesn't have to be dirt. It can be grass, dust, mud, puddles of water, shag carpet, or the outline when dust or leaves stops when they meet resistance. It doesn't matter what is leaving the signs. It's RAW that players can detect invisible based on non-visual perceptions and visual perception cause by the invisible person such as tracks. It's raw that perception detects what might normally go unnoticed. It's RAW that characters have passive perception.

The only alternative is to ignore the RAW. Ignoring the RAW isn't a demonstration that the RAW doesn't exist.

[Cybren]

It doesn't have to be dirt. It can be grass, dust, mud, puddles of water, shag carpet, or the outline when dust or leaves stops when they meet resistance. It doesn't matter what is leaving the signs. It's RAW that players can detect invisible based on non-visual perceptions and visual perception cause by the invisible person such as tracks. It's raw that perception detects what might normally go unnoticed. It's RAW that characters have passive perception.

The only alternative is to ignore the RAW. Ignoring the RAW isn't a demonstration that the RAW doesn't exist.

Characters have passive perception, but the unconscious character has no stealth roll, because they can't take actions to roll stealth. By your reading of the rules the unconscious invisible person is always automatically noticed, from any distance.

[Cazero]

In that case, the wizard would make a stealth check and it would be opposed by the passive perception of anyone entering the room (or a roll of those entering were actively trying to look for hidden items/creatures).
The reading wizard isn't actively hiding. Why roll a dice? Use passive stealth and give him advantage on it until someone use active perception or bump into him.

[MaxWilson]

I can only quote that it is impossible for the party to see him in response to item 1 so many times. The party cannot see him unless they can see invisibility somehow.

Oh, come on. Stop the pedantry. You can't argue on the one hand that PCs will see "body-sized impressions in the dirt" and in the next breath pretend you've been painstakingly avoiding all cases of "seeing" invisible creatures. You know exactly what I was asking.

[Segev]

This is specific to the invisible condition.

"The creature’s location can be detected by any noise it makes or any tracks it leaves. "

Specific beats general.

Your quote is being misapplied. The party will automatically fail to see him, correct; they will not automatically fail to hear or smell him, or fail to see visible signs of his presence such as the footprints that were specifically mentioned. In no case is the party detecting the invisible person by visual means because it's impossible to see the invisible person by visible means as per the description of the invisibility description, thus completely invalidating your whole argument because it's not a sight based check and never was. ;)

Eh. I think you're grasping at straws, here.

If an invisible wizard is leaning on the wall in a room and you walk in, then it is ludicrous to assume that you automatically hear his breathing sufficiently to know that he's there. Just as you might require a perception check to notice that there is a coin on the floor, you can require a perception check before somebody notices the wizard's breathing, or the depression in the shag carpet where he's standing, or what-have-you. There is absolutely no reason to assume that the invisible wizard is just as easily noticed as he would be if he were visible.

I don't know about you, but I wouldn't require a perception check to notice a wizard leaning against a wall if he were visible; I'd describe him as part of the description of the room. I would, however, not automatically include "and there's somebody breathing at normal breathing volume and pace over next to the wall" into a description of a room that included our wall-leaning invisible wizard.

Now, if it makes you more comfortable, you can assume that anybody who is NOT making enough noise to draw attention to themselves is "hiding," and thus have the wizard roll a stealth check.

If there is any hole in the RAW, though, it's if you force the wall-leaning invisible wizard to make a stealth check, because the Invisible condition offers no bonuses to stealth, so somehow the wall-leaning invisible wizard is easier to spot than a coin on the floor that you decided was "moderately" hard to spot (DC 15)...because the wall-leaning invisible wizard has a dex of 12 and no proficiency in stealth.

So, you can force an interpretation of the rules which creates some nonsensical holes, but if you do so, it's your fault for forcing that interpretation, rather than the game's fault. 5e is - for better or worse - very open to interpretation. When you have the liberty to interpret it such that things make sense and work, it's recommended that you take it.

[CursedRhubarb]

Last game day I had to use invisibility to sneak my terrified lil dwarf biscuits out of an army camp after setting off an alarm. Going invis in front of people did squat for me since I was seen doing it, but as soon as I moved I got my stealth checks to slip out and away. It got me past the humans but the dogs could still smell me (completely forgot to prestidigitation my smell away) so had to do some fancy footwork to get upwind so I could beat the dogs' perception (smell) checks before they caught me.

Invisibility can be super useful but it's not an instant win button. Still have to do some quick thinking to what else can give you away and make those stealth checks a lot harder.

[Segev]

Last game day I had to use invisibility to sneak my terrified lil dwarf biscuits out of an army camp after setting off an alarm. Going invis in front of people did squat for me since I was seen doing it, but as soon as I moved I got my stealth checks to slip out and away. It got me past the humans but the dogs could still smell me (completely forgot to prestidigitation my smell away) so had to do some fancy footwork to get upwind so I could beat the dogs' perception (smell) checks before they caught me.

Invisibility can be super useful but it's not an instant win button. Still have to do some quick thinking to what else can give you away and make those stealth checks a lot harder.

Indeed. And I don't think this scenario is one about which anybody's arguing: you absolutely had to make stealth checks.

(I do think it would be nice if Invisibility gave you advantage or a bonus to such checks, though.)

What is in dispute is whether you should automatically (based on passive perception being greater than zero) know that there is an invisible person in a room you just entered, and right where he is so you can walk up and swing a sword through his space (with disadvantage on the attack roll). Or if something has to happen to at least trigger a need for a stealth check.

[Ashrym]

I'm not being pedantic nor am I grasping at straws. Those are the rules. They are RAW and they have been quoted. The only argument against them has been to ignore them.

As written, invisible can be detected because it's not inaudible, intangible, or scent-free. That's only one sense is having issues and the game applies the advantage mechanic to combat because of it.
As written, perception is not just visible. It's a variety of senses. As written it applies to things that would normally go unnoticed. As written, it's a passive ability and and therefore on.

The arguments were that there wasn't RAW. That is clearly false. RAW was just being ignored.

The following arguments simply disputed that there was actually any noise or movement or visual clues even though invisibility shows this isn't the case under it's description. That's the equivalent of "LA!LA!LA!LA!LA!LA!LA!" with fingers in ears from the opposing debaters. This is proven in the invisibility description, perception description, passive perception description, and chapter 8 on using passive perception. All of those apply to the invisible condition.

The next argument is stating the arguments are pedantic or grasping at straws. That's an attack directed at me and in no way invalidates the points I have proven. If that's what the opposing debaters have fallen towards it tends to show a lack of ability to refute the actual RAW.

The only valid argument was a DM can do things based on how he or sees things. That part is true, but a DM who is ignoring the passive perception mechanic is still ignoring the RAW in doing so. A DM not following the invisibility condition description and passive perception mechanics does not demonstrate the lack of existence of those mechanics. It's the equivalent of "because we say so" and a poor argument as well.

I can hear someone casually breathing. It's not a stretch. It became noticeable as a parent. Someone used to watching out for danger and more perceptive than me in a fantasy setting is much less of a stretch. It's not me being pedantic or grasping at straws. It's those of you casting the first stone. ;-)

[Segev]

I have not once argued that the invisible person is (magically) silent, without odor, or intangible. I have argued that walking into a room, you are no more likely to notice the telltale signs of his presence (barring him being notably loud or doing something obvious like kicking up dust) than you are to notice a random coin on the floor. Sure, you might, but it's not going to be against the DC 4 that might be generated by demanding a "stealth" check from a wizard.

If you ever have a perception roll required to notice things which are INCAPABLE OF TAKING ACTIONS because they're not obvious, then you should require a similarly difficult perception roll for noticing the invisible wizard leaning against the wall.

Under certain circumstances - the invisible wizard is actually levitating a foot off the ground, and there's conversation going on that echoes around the room and drowns out softer sounds, and you don't happen to have a dog's sense of smell - I wouldn't even allow the roll unless the players actively took steps to search for such things.

This is because, explicitly, when sight is the sense that allows you to detect the wizard, you cannot detect the wizard. Per the RAW.


So perhaps what we're really looking at here is a much higher DC, since senses other than sight are not really honed to detect people who aren't moving around and/or talking. Pity we don't have example DCs anywhere in the PHB or DMG; we're left to guess whether that goes from DC 0 to DC 25 based on losing that one sense.

[krugaan]

Can we just link to the old thread and be done with it?

Not to attempt to stifle debate, but really, this is a well worn path.

Like, several Grand Canyons worth.

[MaxWilson]

Can we just link to the old thread and be done with it?

Not to attempt to stifle debate, but really, this is a well worn path.

Like, several Grand Canyons worth.

No, I think this is new. Usually the debate is about whether Invisibility automatically makes you hidden in combat, but Ashrym here is going a step further: he's arguing that player characters automatically perceive everything in their environment which isn't taking the Hide action including unconscious invisible creatures. That's pretty novel. Have there really been previous threads on this topic?

It's true though that this horse is pretty thoroughly dead. I just don't think there have been previous threads on the subject to which one could link.

[CantigThimble]

The way I'd rule it is to take the DC of seeing whatever invisible thing it is and increase the DC by 5 or so. Then if your passive perception beats that new DC then you notice it. The stealth skill of whoever you're looking for wouldn't come into account until the invisible guy tried to hide. For example, large or heavily armored creature, probably DC 5 depending on what they were doing. That goes up to DC 10, so most people would notice that something was up unless they were exceptionally oblivious. A regular person might be DC 10 + 5 so only reasonably perceptive people would notice them by default. Depending on size, armor and what they were doing I might adjust those slightly.(also passive stealth bonuses like boots of elvenkind or something) In combat, if someone was aware that an invisible person was present I'd probably have them roll every round without using their action, though the actions people take in combat would be likely to lower the DC of noticing the invisible guy as well.

Basically, my thinking is that game mechanics making intuitive sense and not confusing people out of the moment in the game is much more important than maintaining the default character power levels or absolute strict RAW. Also, it's very likely that different classes are already unbalanced, though fortunately they're unbalanced subtly enough that people aren't certain how so adding another small change in power level is a pretty low cost for a significant increase in intuitive gameplay. If I were absolutely certain what imbalances exist I would be much more wary about these kinds of power adjustments but I'm not.

[BiPolar]

No, I think this is new. Usually the debate is about whether Invisibility automatically makes you hidden in combat, but Ashrym here is going a step further: he's arguing that player characters automatically perceive everything in their environment which isn't taking the Hide action including unconscious invisible creatures. That's pretty novel. Have there really been previous threads on this topic?

It's true though that this horse is pretty thoroughly dead. I just don't think there have been previous threads on the subject to which one could link.

I think it depends on the scenario (as has been said of combat vs. out of combat). If they're just walking into a random room in a town, I wouldn't expect them to be constantly looking for signs of invisibility. If they're dungeon crawling or in an area where they're expecting possible combat, then I'd say that their passive perception is on and they can roll to see if they see anything.

[IShouldntBehere]

No, I think this is new. Usually the debate is about whether Invisibility automatically makes you hidden in combat, but Ashrym here is going a step further: he's arguing that player characters automatically perceive everything in their environment which isn't taking the Hide action including unconscious invisible creatures. That's pretty novel. Have there really been previous threads on this topic?



Yes. It's a road that they've been down this road before. Anyway, I'm wondering where people would go with this:


Imagine you are sitting on an invisible platform in the middle of enclosed white sphere, 100 light years in diameter. The invisible platform extends from you to all edges of the sphere, essentially making a 100 light year diameter circular surface all around you. Besides being invisible, and immune to all forms of structual collapse or decay it otherwise behaves like 1" thick marble floor. All points in the sphere are magically under the effects of ideal "Bright Light" for human vision. The sphere is filled with ordinary air, but not other dust or earthly debris

Aside from being ageless and immune detrimental effects of eternal isolation, you are human. At five random points alongside the outside of the sphere spawn five different guys, similarly ageless but otherwise human beings pop into existence:

1) Carl: Carl is invisible, but sings Taylor Swift's "Shake it Off" at the top of his lungs for all eternity.
2) Pete: Pete is invisible, and walks normally but makes no particularly special attempt to be stealthy.
3) Bob: Bob is not invisible, and walks normally as Pete does.
4) Stan: Stan is not invisible, and sings Taylor Swift's "Blank Space" at the top of his longs for all ternity.
5) Eric: Eric is invisible, and tries his darnedest every round to be stealthy but is almost rolls a "1" on his check.


Your passive perception is 15. All 5 begin advancing at you at the same rate from the edge of the sphere:

At what distance do you notice Carl?
At what distance do you notice Pete?
At what distance do you notice Bob?
At what distance do you notice Stan?
At what distance do you notice Eric?

Assume you are also armed with a magic bow with range 100light years/200light years. It in no way aids your senses or aim, but can fire at any you can single out in the same fashion as an ordinary one. The arrows from the bow being magic, traverse any distance in the span of one round (6 seconds) and avoid any pesky explosions, implosions or ripping your arm off from infinite force associated from a projectile moving so fast.

At what distance can you make attack rolls against Carl?
At what distance can you make attack rolls against Pete?
At what distance can you make attack rolls against Bob?
At what distance can you make attack rolls against Stan?
At what distance can you make attack rolls against Eric?

EDIT: If the answers to any of these vary due to any of skill or ability check(s), feel free to explain what those checks are when they take place and what the consequences are.

[Vogonjeltz]

So, I was on the raw thread with a question and got this prompt reply:


Quote Originally Posted by Dmdork View Post
Q457 if a creature is invisible and like 20feet away, can I walk up to it and attack it, albeit with disadvantage?
A457-Yes. Unless the invisible creature takes the Hide action and their Stealth score beats the Perception of the attacker.

This doesn't sit well with me. I hope one of you can help me to understand how this is plausible. It seems like invisibility doesn't give you so much. It's the same with blindness. Blindness/invisibility do not effect your movement rate. Why? I understand keeping it simple, but this seems unrealistic

Dexterity (stealth) checks represent an attempt by the creature in question to hide from sight and remain unheard.

The basic assumption being, if you aren't actively trying to avoid making noise, you're going to be audible (i.e. people in the room hear you walking around over there on the left). If you don't try to hide then you're going to leave obvious clues like footprints in the dust/dirt, splashing around in water, etc...

Being invisible doesn't make the character silent (their equipment probably makes noise, walking or running still makes a racket, etc...), and it doesn't remove traces of their existence (a shape in the rain/snow, footprints, kicking up dust/water, etc...).

Why would invisibility interfere with your movement?

I had thought there was something in the PHB along the lines of it being difficult terrain if you can't see...maybe I misremember.


There's also an interpretation that basically gives all humans hyper-sonar such that in a pitch black room everyone knows the exact location of everyone else who isn't actively sneaking around. No my bag, but hey to each their own.

It's called Sound Localization, not "hyper-sonar". It's science, not magic.

https://en.wikipedia.org/wiki/Sound_localization#Sound_localization_by_the_human _auditory_system


There is no such rule. There is no guarantee anywhere that a PC will automatically see a person or object that is not deliberately hidden.

In point of fact the DMG has a rule on when encounters begin that states that any creature not trying to hide is automatically noticed by the opposing side. Not seen, but noticed.

So there's at least one rule. I would imagine there are probably several others in the PHB as pertaining to hiding.

If you're hinging the argument on literally seeing the creature themselves, then that's a non-starter because it wasn't what the person you quoted was arguing, nor even the portion you bolded, which was about the location, not the creature themselves.

[Segev]

Believe it or not, identifying the "square" something is in by the sounds it makes is actually very hard. It's doable, but it's not trivial. A friend of mine in college was part of a group that designed a chamber for testing this, in fact. Aim at the right region, and you "hit" (no "disadvantage" or the like). But all you had was sound, not vision, to aim with.

[CursedRhubarb]

If someone or something has gone through the trouble of becoming invisible in some way, wouldn't common sense point to them doing so in order to be stealthy or to hide in which case they should have a decent to high DC for your passive to beat to even know something is there? Unless they had it done to them against their will or are something/someone powerful enough not to care if they are found or not and are invisible just to mess with people. If something is invisible and not trying to hide or sneak this could lead to:

I attack the invisible creature with my sword!

*High AC, you miss, pit find eats your face, you have died*

*Low AC and you hit as your party watches you murder a small child that had a spell put on them.*

[IShouldntBehere]

It's called Sound Localization, not "hyper-sonar". It's science, not magic.

https://en.wikipedia.org/wiki/Sound_localization#Sound_localization_by_the_human _auditory_system



...and in humans it doesn't have the kind of resolution or update frequency require for what's discussed in this thread. You can test this simply: Get a boffer, wiffle bat, or baguette (or other safe bopping implement of your choice), a friend and a blindfold and head to the nearest gymnasium or field. Blind fold yourself then call for your friend to approach you at a distance, and just casually jog around around the area in a random fashion making no real effort to be sneaky... just jogging around.

Then try to hit them with your wiffle bat, boffer or baguette while they move around. You will not hit them. You will not come close to hitting them. You'll be lucky not to trip and fall on your face.

Then try it with them ringing a cowbell, or singing your national anthemn at the top of their lungs. You'll get closer but still not ever hit them.

Record your results! You'll see that for an ordinary every day joe human hearing is not a precise enough sense to even come close to hitting their 5' square, let along actually targeting their body.

One could argue that D&D characters are better than the average joe human, but now we're back to them having sonar rather than ordinary human hearing. Which is fine if that's how capable you like your fantasy humans to be.

[Ashrym]

I have not once argued that the invisible person is (magically) silent, without odor, or intangible. I have argued that walking into a room, you are no more likely to notice the telltale signs of his presence (barring him being notably loud or doing something obvious like kicking up dust) than you are to notice a random coin on the floor. Sure, you might, but it's not going to be against the DC 4 that might be generated by demanding a "stealth" check from a wizard.

I never said you were arguing that. I said that's what it takes to avoid the other aspects of perception beyond visual. And you are mistaken as per my quote of the rules. Perception is noticing things like that right under the description of perception when the description mentions noticing thing that normally go unnoticed. The text says it. You ignore it. The 4 is just something you made up and not what I said either. That's a strawman approach.

Perception includes perceiving things that normally go unnoticed, which is the little things. Adding other things that are more obvious doesn't change that.


If you ever have a perception roll required to notice things which are INCAPABLE OF TAKING ACTIONS because they're not obvious, then you should require a similarly difficult perception roll for noticing the invisible wizard leaning against the wall.

The object incapable of taking actions displaces space. Dust will settle on the ground around it but not under it. Characters will see the difference. The object incapable of taking actions also does not breath and allow for hearing it. The invisibility spell can't actually be cast on an object, for that matter. It's cast on a creature per that description.

What you are attempting to say is that the invisible wizard reading a book is as silent and motionless as an inanimate object, which obviously isn't true; it's actually rather preposterous. However, if it was true, there can still be signs of the object based on what does or doesn't change by it's presence in the environment.


Under certain circumstances - the invisible wizard is actually levitating a foot off the ground, and there's conversation going on that echoes around the room and drowns out softer sounds, and you don't happen to have a dog's sense of smell - I wouldn't even allow the roll unless the players actively took steps to search for such things.

The wizard cannot be invisible and levitate because he needs concentration for each, and it's obviously becoming more contrived as you try to make a point stressing environmental factors regardless of the rules as clearly written. That's pushing the goal post. The first thing I would wonder is why the wizard is bothering to be invisible or levitate just to read a book, and where the conversation is coming from, and that he's cleaning bathed but still doesn't stand out as cleanly bathed, and after having contrived such a condition just to try an make your point you would still fail in acknowledging the 2 key things you choose to ignore: passive perception is a thing, and perception catches those details that would normally have not been noticed.

The conversation that echoes is an obvious example that the characters perceptions are always on. It's not like they need a check to hear the noises. The check is for hearing the other noises as only fantasy characters might. That little thing that catches their attention regardless of what it is. That's what the passive perception roll would be for in the first place.

I agree that you can be withing your right as a DM to state the characters would have trouble hearing the invisible floating scentless person with a lot of background noise in a situation created solely to try and eliminate clues that exist per the invisibility condition. It's clear you want that person to be invisible for whatever reason. That's not the point. The point is that there are clues and it doesn't take visual perception for them to exist and there are visual clues as well that aren't covered by the invisibility. That's still why a passive (ie it's always on) ability applies the way it does.

Passively hiding would likely be the thing to use because no actions are being taken, and disadvantage on the perception based on the environmental issues you've stacked on, but that doesn't mean player perception is somehow turned off.


This is because, explicitly, when sight is the sense that allows you to detect the wizard, you cannot detect the wizard. Per the RAW. And this is where your argument falls into the toilet. This is because, explicitly, perception isn't using sight to see the invisible wizard. Invisibility explicitly states the character cannot see the wizard without some means to see invisibility. That's RAW right in the description for invisibility. If the character isn't using sight to see the wizard and is instead using sight to see the environment around the wizard and using other senses to detect the wizard as well your argument falls on it's face. Explicitly. Go read invisibility, perception, and passive perception again. Ignoring those specifics doesn't make your statement RAW. It makes the rules pertaining your statement incomplete.


So perhaps what we're really looking at here is a much higher DC, since senses other than sight are not really honed to detect people who aren't moving around and/or talking. Pity we don't have example DCs anywhere in the PHB or DMG; we're left to guess whether that goes from DC 0 to DC 25 based on losing that one sense.

I'm not going to argue a adjusting based on environment. In your example, which I consider extreme, I might have gone with a passive check on the wizard as stated and disadvantage on a passive check for the characters. If you really pushed it you could add advantage on a passive check for the wizard as well. I'm inclined not to when characters are perfectly capable of detecting invisible creatures actually trying to be stealthy in the midst of battle (which is a big reason why the wizard not trying to be stealthy doesn't make sense to be so hard to detect) following the same rules.

That would look something like 10 + dex mod + prof bonus (if proficient in stealth) + 5 (passive advantage bonus if applied) for anywhere from 10-26 on the DC, depending, for the wizard. I would have gone with the most likely 10 + dex mod for 12 as the DC, tbh. The party would be the standard passive perception. For normal people that's 10 and would fail. Even the typically wise characters would need wisdom 16 to make that check because the tie would go to the wizard.

Only a combination of perception proficiency (ie skilled at detecting things others would miss) plus a wisdom bonus would make it possible for low level character to detect that. If the DM does apply disadvantage that's a -5 penalty on the passive perception check so it would take a combination of +8 from proficiency and wisdom bonus to make that.


No, I think this is new. Usually the debate is about whether Invisibility automatically makes you hidden in combat, but Ashrym here is going a step further: he's arguing that player characters automatically perceive everything in their environment which isn't taking the Hide action including unconscious invisible creatures. That's pretty novel. Have there really been previous threads on this topic?

It's true though that this horse is pretty thoroughly dead. I just don't think there have been previous threads on the subject to which one could link.

No, I'm arguing that players automatically perceive their environment. An invisible person not actively trying not to be perceived should be perceived somehow, invisible or not per the rules for invisibility. If he's trying not to be perceived that would be the passive check and not automatic perception.

The rules for invisibility aren't different. They clearly state invisible can be detected even though it cannot be seen. How it's detected is different than seeing it and because it's not seen it has some listed advantage / disadvantage benefits.

That gets back to the RAW existing and you choose not to use it for your own reasons.

[MaxWilson]

No, I'm arguing that players automatically perceive their environment. An invisible person not actively trying not to be perceived should be perceived somehow, invisible or not per the rules for invisibility. If he's trying not to be perceived that would be the passive check and not automatic perception.

AFAICT, that's exactly what I said you were saying.

[IShouldntBehere]

The rules for invisibility aren't different. They clearly state invisible can be detected even though it cannot be seen. How it's detected is different than seeing it and because it's not seen it has some listed advantage / disadvantage benefits.

That gets back to the RAW existing and you choose not to use it for your own reasons.

Up-thread a bit I give an example of the five dudes approaching over long distances. If you were ruling, when would you rule each is detected in the scenario framed?

[krugaan]

No, I think this is new. Usually the debate is about whether Invisibility automatically makes you hidden in combat, but Ashrym here is going a step further: he's arguing that player characters automatically perceive everything in their environment which isn't taking the Hide action including unconscious invisible creatures. That's pretty novel. Have there really been previous threads on this topic?

It's true though that this horse is pretty thoroughly dead. I just don't think there have been previous threads on the subject to which one could link.


Yes. It's a road that they've been down this road before. Anyway, I'm wondering where people would go with this:


Imagine you are sitting on an invisible platform in the middle of enclosed white sphere, 100 light years in diameter. The invisible platform extends from you to all edges of the sphere, essentially making a 100 light year diameter circular surface all around you. Besides being invisible, and immune to all forms of structual collapse or decay it otherwise behaves like 1" thick marble floor. All points in the sphere are magically under the effects of ideal "Bright Light" for human vision. The sphere is filled with ordinary air, but not other dust or earthly debris

Aside from being ageless and immune detrimental effects of eternal isolation, you are human. At five random points alongside the outside of the sphere spawn five different guys, similarly ageless but otherwise human beings pop into existence:

1) Carl: Carl is invisible, but sings Taylor Swift's "Shake it Off" at the top of his lungs for all eternity.
2) Pete: Pete is invisible, and walks normally but makes no particularly special attempt to be stealthy.
3) Bob: Bob is not invisible, and walks normally as Pete does.
4) Stan: Stan is not invisible, and sings Taylor Swift's "Blank Space" at the top of his longs for all ternity.
5) Eric: Eric is invisible, and tries his darnedest every round to be stealthy but is almost rolls a "1" on his check.


Your passive perception is 15. All 5 begin advancing at you at the same rate from the edge of the sphere:

At what distance do you notice Carl?
At what distance do you notice Pete?
At what distance do you notice Bob?
At what distance do you notice Stan?
At what distance do you notice Eric?

Assume you are also armed with a magic bow with range 100light years/200light years. It in no way aids your senses or aim, but can fire at any you can single out in the same fashion as an ordinary one. The arrows from the bow being magic, traverse any distance in the span of one round (6 seconds) and avoid any pesky explosions, implosions or ripping your arm off from infinite force associated from a projectile moving so fast.

At what distance can you make attack rolls against Carl?
At what distance can you make attack rolls against Pete?
At what distance can you make attack rolls against Bob?
At what distance can you make attack rolls against Stan?
At what distance can you make attack rolls against Eric?

EDIT: If the answers to any of these vary due to any of skill or ability check(s), feel free to explain what those checks are when they take place and what the consequences are.

yeah, the title of the thread (at least the particular iteration I remember) was "Echolocation for free" or something like that, and dealt with pretty much this exact scenario, since reductio ad absurdum and all that.

which results in strange arguments like:
- you know the location of everything to an unlimited range
- objects in the world all take the "hide" action every turn
- etc.

[Coffee_Dragon]

It allows you to hide without a hiding place.

I went to the rock to hide my face
And the rock cried out, "No hiding place"
And I said, "Screw you, rock, I'm invisible"

[Ashrym]

Up-thread a bit I give an example of the five dudes approaching over long distances. If you were ruling, when would you rule each is detected in the scenario framed?


NOTICING OTHER CREATURES
While exploring, characters might encounter other creatures. An important question in such a situation is who notices whom. Indoors, whether the sides can see one another usually depends on the configuration of rooms and passageways. Vision might also be limited by light sources. Outdoor visibility can be hampered by terrain, weather, and time of day. Creatures can be more likely to hear one another before they see anything. If neither side is being stealthy, creatures automatically notice each other once they are within sight or hearing range of one another. Otherwise, compare the Dexterity (Stealth) check results of the creatures in the group that is hiding with the passive Wisdom (Perception) scores of the other group, as explained in the Player's Handbook.

This is another reiteration of the rules. If the invisible wizard isn't being stealthy, the party automatically notices him once they are within hearing range. On a similar note, the DMG also states the party automatically detects hazards unless they have been hidden.

Within hearing range takes more work and consideration of the environment. If this were an eagle totem barbarian with the eyesight ability he can see quite well from quite far away and I would give him better range on visual cues. Audible cues not so much.

I don't recall your example, but invisible outside of standard audible range means the visibility range sucks. This is where the environment and DM judgements come more into play. I don't think anyone is stating unlimited range on senses. Then again, if we're suddenly moving the invisible wizard who is concentrating on two spells at once outside and still giving him a loud conversation from down the hall even though he's outside it... wait, that example became way too complicated to further complicate.

RAW: The party can detect the wizard and if the wizard isn't trying to be stealthy the party automatically detects the wizard within hearing range.

If your example is outside of sensory range then I wouldn't bother with a detecting automatically if the person was not trying to be stealthy or making the check if the person was trying to be stealthy. Outside of range is still outside of range. There are also penalties based on movement rate.

[IShouldntBehere]

This is another reiteration of the rules. If the invisible wizard isn't being stealthy, the party automatically notices him once they are within hearing range. On a similar note, the DMG also states the party automatically detects hazards unless they have been hidden.

Within hearing range takes more work and consideration of the environment. If this were an eagle totem barbarian with the eyesight ability he can see quite well from quite far away and I would give him better range on visual cues. Audible cues not so much.

I don't recall your example, but invisible outside of standard audible range means the visibility range sucks. This is where the environment and DM judgements come more into play. I don't think anyone is stating unlimited range on senses. Then again, if we're suddenly moving the invisible wizard who is concentrating on two spells at once outside and still giving him a loud conversation from down the hall even though he's outside it... wait, that example became way too complicated to further complicate.

RAW: The party can detect the wizard and if the wizard isn't trying to be stealthy the party automatically detects the wizard within hearing range.

If your example is outside of sensory range then I wouldn't bother with a detecting automatically if the person was not trying to be stealthy or making the check if the person was trying to be stealthy. Outside of range is still outside of range. There are also penalties based on movement rate.

My example isn't outside sensory range as my example has them approaching you and the question is "When do you detect them"? They are starting at an absurdly long range but since they are approach you, they will eventually reach you and bump into you directly (which I'd hope anyone would notice). Actually it's two question "When do you notice them" and "When you can you start making attacks against them".

This is obviously some time between they appear (100 light years away) and when they are bumping into you (0 inches away). I'm simply asking where you'd put that transition for each them, given their respective behavior.

[MaxWilson]

Yes. It's a road that they've been down this road before. Anyway, I'm wondering where people would go with this:


Imagine you are sitting on an invisible platform in the middle of enclosed white sphere, 100 light years in diameter. The invisible platform extends from you to all edges of the sphere, essentially making a 100 light year diameter circular surface all around you. Besides being invisible, and immune to all forms of structual collapse or decay it otherwise behaves like 1" thick marble floor. All points in the sphere are magically under the effects of ideal "Bright Light" for human vision. The sphere is filled with ordinary air, but not other dust or earthly debris

Aside from being ageless and immune detrimental effects of eternal isolation, you are human. At five random points alongside the outside of the sphere spawn five different guys, similarly ageless but otherwise human beings pop into existence:

1) Carl: Carl is invisible, but sings Taylor Swift's "Shake it Off" at the top of his lungs for all eternity.
2) Pete: Pete is invisible, and walks normally but makes no particularly special attempt to be stealthy.
3) Bob: Bob is not invisible, and walks normally as Pete does.
4) Stan: Stan is not invisible, and sings Taylor Swift's "Blank Space" at the top of his longs for all ternity.
5) Eric: Eric is invisible, and tries his darnedest every round to be stealthy but is almost rolls a "1" on his check.

Your passive perception is 15. All 5 begin advancing at you at the same rate from the edge of the sphere:

At what distance do you notice Carl?
At what distance do you notice Pete?
At what distance do you notice Bob?
At what distance do you notice Stan?
At what distance do you notice Eric?

Assume you are also armed with a magic bow with range 100light years/200light years. It in no way aids your senses or aim, but can fire at any you can single out in the same fashion as an ordinary one. The arrows from the bow being magic, traverse any distance in the span of one round (6 seconds) and avoid any pesky explosions, implosions or ripping your arm off from infinite force associated from a projectile moving so fast.

At what distance can you make attack rolls against Carl?
At what distance can you make attack rolls against Pete?
At what distance can you make attack rolls against Bob?
At what distance can you make attack rolls against Stan?
At what distance can you make attack rolls against Eric?

EDIT: If the answers to any of these vary due to any of skill or ability check(s), feel free to explain what those checks are when they take place and what the consequences are.

Okay, I'll bite. For purposes of this answer I'm going to assume that all Taylor Swift songs are equivalent to each other and to any other loud shouting.

#3 and #4 (not invisible) are easily detected at a distance of 1.5 miles, and if they are wearing dark clothing against this infinite (completely level) white background I'd probably call it 20 miles. I'm AFB but I believe that's congruent with both DMG guidelines for visibility on from mountaintops, and with what little I know about nautical vision distances. Detection = localization for a visible target, so attack rolls can be commenced immediately.

#1 (invisible, loudly singing continuously) is easily detected from (arbitrary guesstimate here based on quick Internet research; this guesstimate errs intentionally on the generous side) 1 mile away. Since we're playing D&D I'll be equally generous with the attack rolls and say he's localized immediately and you can attack him immediately. Yes, I know it's amazing and bizarre, but it's no more amazing really than some of the other feats performed by fighters in D&D such as leading a moving target perfectly regardless of its speed. You can come up with physical, magical, or biological theories if you like to explain how D&D humans are able to perform such feats, and some of them may even be true.

#2 (invisible, walking calmly) is easily detected from about 30-60' away (for Perception 15 I'd make it 30'), or maybe as far as 300' if he's a particularly noisy walker (boisterous clomping). He is localized immediately as soon as you detect him.

#5 (invisible, stealthy, bad at stealth)... I'd call this identical to #2. Detected at 30'-60' depending on conditions. Localized immediately, can be attacked immediately.

[Malifice]

Characters have passive perception, but the unconscious character has no stealth roll, because they can't take actions to roll stealth. By your reading of the rules the unconscious invisible person is always automatically noticed, from any distance.

So the DM just sets a fixed DC. Like he would for a secret door, a faint sound or any other hidden or hard to detect object that isnt immediately obvious.

If the PCs passive perception (or active, either way) beats the DC, they hear him breathing heavily, the rustle of his robes as he moves in his sleep, notice the outline in the carpet/ dirt/ dust/ grass, smell his spices, bat guano, and other weird components of his spell compononent pouch, or smell his sweat from not bathing in days, notice the blood on the floor where he lays looks very odd, and seems to be coming from no-where, gets a 'feeling' that they're not alone or whatever.

Invisibility takes out one sense. We have others. 'Perception' accounts for all 5 (or 6) and the ability to deduce from those senses that something is going on.

If you and I were sword fighting (and you were wearing plate mail, or adventuring equipment, or even just a long stave indoors) and suddenly became invisible, I could certainly keep swinging like mad in your general vicinity, and I would notice your feverish blocks of my wild sword swings. I could probably tell where you went if you ran off by simply listening (or if indoors by looking at the floor, or the swirl of dust or smoke from a lantern). I might not of course (if you were actually trying to be silent and conceal your presence from me in combat, you would of course be taking the Hide action, and making a Stealth check... my ability to detect you from that point will depend on how sneaky you are, and how perceptive I am).

Invisibility isnt the 'autowin' it used to be.

Unless of course its cast on or by a Rogue (such as an arcane trickster). That guy has expertise in Stealth and can Hide as a bonus action, meaning he can cast it and Hide all in the same turn (and thanks to a high Dex and Expertise in Stealth will almost certainly be able to render himself immune to any attacks, barring a lucky guess from his opponent). Layer on improved invisibility, and assured skill at 11th level, and he becomes a total nightmare.

I find the rule is both realistic, and useful from a gamist position. It generally means that you're better off casting invisibility on the Rogue (to make use of his stealth abilities) rather than casting it on yourself. It also means a caster cant simply invalidate the Rogue by granting himself an infinite stealth check result.

It was things like that (knock, detect traps, invisibility) that led to casters being such a high tier in earlier editions of the game; they could invalidate other classes by doing their job better.

Those days are gone.

[georgie_leech]

So the DM just sets a fixed DC. Like he would for a secret door, a faint sound or any other hidden or hard to detect object that isnt immediately obvious.


Honestly, I think this is the first time I've seen you take this position, and I find it agreeable with how I would run things. This is a far cry from 'immediately notice unless the Hide action is taken,' without turning it into an auto win out of combat. This is good and fine by RAW. There is some doubt as to whether success is guaranteed (people might or might not notice faint sounds, smells, or visual oddities like indents in carpet), there are consequences for failure (not noticing the invisible whatever), and the DM calls for a check.

[RickAllison]

I can't be the only one who is now considering having the PCs in a room where they intermittently hear the pages of a book turning and can't see where it came from. It is just too good of paranoia fodder to pass up!

[Malifice]

Honestly, I think this is the first time I've seen you take this position, and I find it agreeable with how I would run things. This is a far cry from 'immediately notice unless the Hide action is taken,' without turning it into an auto win out of combat. This is good and fine by RAW. There is some doubt as to whether success is guaranteed (people might or might not notice faint sounds, smells, or visual oddities like indents in carpet), there are consequences for failure (not noticing the invisible whatever), and the DM calls for a check.

I was referring to the situation of the unconscious invisible wizard. All things being equal, a DC 15 seems about right to detect him lying KOed on the floor. Plush carpet or grass, and its probably a DC 10. He's a Halfing in a large room, and a DC 20 sounds fair.

If a Wizard cast invisibility and wanted to be [quiet, conceal his presence, mask his odor, move silenty, sneak away] he has to make me a Steath check (accomplished via the Hide action if in combat). If he fails to nail the passive Perception DC for the Stealth check, he makes enough noise, or smell, or disturbs the smoke/ dust, or leaves footprints in the carpet/ dust/ dirt/ mud/ grass, or brushes past his perceptive foe, which enables an attack to be made against him (at disadvantage), although he is still immune to attacks of opportunity and most spells.

If he passes the Stealth check, he cant be attacked or targetted at all barring a Perception check (via the Search action if in combat) or via a very lucky guess.

Its no different to if he ducked behind a wall, or into a patch of darkness.

In practice it works fine. I think its the best way they've done invisibility in any edition so far.

[BiPolar]

How can the wizard be unconscious and invisible? Or is this a case where someone else is cast it on him?

[CursedRhubarb]

Okay, I'll bite. For purposes of this answer I'm going to assume that all Taylor Swift songs are equivalent to each other and to any other loud shouting.

#3 and #4 (not invisible) are easily detected at a distance of 1.5 miles, and if they are wearing dark clothing against this infinite (completely level) white background I'd probably call it 20 miles. I'm AFB but I believe that's congruent with both DMG guidelines for visibility on from mountaintops, and with what little I know about nautical vision distances. Detection = localization for a visible target, so attack rolls can be commenced immediately.

#1 (invisible, loudly singing continuously) is easily detected from (arbitrary guesstimate here based on quick Internet research; this guesstimate errs intentionally on the generous side) 1 mile away. Since we're playing D&D I'll be equally generous with the attack rolls and say he's localized immediately and you can attack him immediately. Yes, I know it's amazing and bizarre, but it's no more amazing really than some of the other feats performed by fighters in D&D such as leading a moving target perfectly regardless of its speed. You can come up with physical, magical, or biological theories if you like to explain how D&D humans are able to perform such feats, and some of them may even be true.

#2 (invisible, walking calmly) is easily detected from about 30-60' away (for Perception 15 I'd make it 30'), or maybe as far as 300' if he's a particularly noisy walker (boisterous clomping). He is localized immediately as soon as you detect him.

#5 (invisible, stealthy, bad at stealth)... I'd call this identical to #2. Detected at 30'-60' depending on conditions. Localized immediately, can be attacked immediately.

Wow...just...wow. you seriously think you can pinpoint the exact location of someone over a mile away? Forget invisibility, I live in clear view of a suburbs area up the mountain just barely over a mile away. An above average person, about 6'5" is between 1.5mm and 2mm tall and less than 1mm wide from that distance visually. You may be able to faintly hear what sounds like it might be a voice if they are as loud as can be and there is absolutely zero interference (aka trees, animal sounds, a shrubbery, wind, creaky old house noise, ambient noise) but you would only be able to tell the general direction it came from and may not even notice the pin point of the person. To say you can instantly locate the exact position of someone invisible at that distance....that's like saying if you stand in the center of the field in Yankee Stadium and there is a clear thumbtack stuck to the back of one of the seats up in the bloody nose section with an iPod playing through headphones in the seat that you would be able to point directly at the thumbtack and know exactly what it is.
Or you think it works like the scene in Hotel Transylvania where the werewolf daughter sniffs the guys scent in the woods and knows instantly what seat he is in while aboard an airplane miles away...

[MaxWilson]

How can the wizard be unconscious and invisible? Or is this a case where someone else is cast it on him?

(1) Wild Magic
(2) Potion
(3) Another caster
(4) Natural invisibility a la Invisible Stalker
(5) Spell research

Note further that in this scenario it isn't really important that it be a wizard specifically. An invisible stalker with zero wizard levels works just as well as an invisible stalker who is a Wizard 10, because all he has to do is lie there in the dirt being unconscious.

========================================


Wow...just...wow. you seriously think you can pinpoint the exact location of someone over a mile away?

Don't confuse a ruling from a DM with that DM's opinion on real-world physics or biology. No, I don't think you could do that, especially not in the terrain you described. Nor do I think you could hit such a person 5% of the time (natural 20) or even 0.25% of the time (natural 20 at disadvantage) if you were shooting at him. Real life isn't D&D.

[Cybren]

Don't confuse a ruling from a DM with that DM's opinion on real-world physics or biology. No, I don't think you could do that, especially not in the terrain you described. Nor do I think you could hit such a person 5% of the time (natural 20) or even 0.25% of the time (natural 20 at disadvantage) if you were shooting at him. Real life isn't D&D.

Well, D&D doesn't have to be real life for someone to want to achieve a certain level of verisimilitude. Using "what a real world person is capable of " is an excellent baseline when the rules have a particular hole, especially when, in the case of things like auditory range, they aren't stated partly because the assumption is a hearing capable person has a particular frame of reference for how hearing works.

In my case, I'd probably rule there's a particular range where they can definitely hear the sound but that's farther off from the range where they could possibly know it's an invisible human and not any other phenomena. Apparently the maximum range at which a human voice is intelligible is about 590'. Let's round that up to 600' and say that in an environment with no other significant ambient distractions you might hear the music but wouldn't be capable of determining that it's an invisible person at all until that range. After that i'd probably have a step-wise progression of the invisible singer having advantage on stealth to escape notice and the hearer having disadvantage on perception to notice them. In the interest of simplicity, let's say it's 600-300-150 Off the top of my head i'd probably just say inside 300' the stealther loses advantage and inside 150' the hearer loses advantage. Not exactly a "totally realism" based ruling, since the numbers are rough fudges, and it still let's someone inside 600' possibly pinpoint a 5sqft area to target with a ranged attack, though. But I'm not going for "totally realistic" just "generally plausible with a pinch of dramatically appropriate"

[MaxWilson]

Well, D&D doesn't have to be real life for someone to want to achieve a certain level of verisimilitude. Using "what a real world person is capable of " is an excellent baseline when the rules have a particular hole, especially when, in the case of things like auditory range, they aren't stated partly because the assumption is a hearing capable person has a particular frame of reference for how hearing works.

I agree. And if I had a DM who ruled that you needed to be closer to pinpoint location, I'd be fine with it. But when I explicitly said, (paraphrasing) "Hey, I'm being generous here in this ruling, and I know it's amazing and weird, and there might even be magical/physical/biological theories to explain the oddity," it's odd to me to have someone jump on that remark asking, "Seriously, you really think that's possible ?!?!!" No, I just try very hard to be generous with my players when in doubt, and I don't think this outcome is problematic enough for me to violate their expectations with a contrary ruling.

All that happened is that someone asked for a ruling on a thought experiment, and each of us is giving our ruling for that thought experiment. It's not even a real situation that is going to arise in play--it's just a hypothetical ruling.


In my case, I'd probably rule there's a particular range where they can definitely hear the sound but that's farther off from the range where they could possibly know it's an invisible human and not any other phenomena. Apparently the maximum range at which a human voice is [i]intelligible is about 590'. Let's round that up to 600' and say that in an environment with no other significant ambient distractions you might hear the music but wouldn't be capable of determining that it's an invisible person at all until that range. After that i'd probably have a step-wise progression of the invisible singer having advantage on stealth to escape notice and the hearer having disadvantage on perception to notice them. In the interest of simplicity, let's say it's 600-300-150 Off the top of my head i'd probably just say inside 300' the stealther loses advantage and inside 150' the hearer loses advantage. Not exactly a "totally realism" based ruling, since the numbers are rough fudges, and it still let's someone inside 600' possibly pinpoint a 5sqft area to target with a ranged attack, though. But I'm not going for "totally realistic" just "generally plausible with a pinch of dramatically appropriate"

Sure, that sounds reasonable too. I have no problem with the methodology you used to arrive at this ruling, or with the conclusion.

Edit: except, it doesn't make sense to give "advantage on stealth" to someone who isn't attempting stealth. Why would you roll Dexterity (Stealth) for someone who isn't trying to sneak? Your proficiency or Expertise in Stealth should be inapplicable.

My rules for stealth somewhat resemble yours--I have the same 600-300-150-ish pattern inspired by Zeno's paradox--but I would only apply it to someone who was actually attempting to go unnoticed, and not for the Accidentally Invisible Loud Man.

[Cybren]

My rules for stealth somewhat resemble yours--I have the same 600-300-150-ish pattern inspired by Zeno's paradox--but I would only apply it to someone who was actually attempting to go unnoticed, and not for the Accidentally Invisible Loud Man.

Ah yes, I had forgotten specifically the premise was dealing with "being non-seeable but nonetheless not trying to hide" and pointing out the contradictions in how the rules use invisibility just as a vector for the hide action rather than a way to escape notice on its own.

[Segev]

I never said you were arguing that. I said that's what it takes to avoid the other aspects of perception beyond visual. And you are mistaken as per my quote of the rules. Perception is noticing things like that right under the description of perception when the description mentions noticing thing that normally go unnoticed. The text says it. You ignore it. The 4 is just something you made up and not what I said either. That's a strawman approach.

Perception includes perceiving things that normally go unnoticed, which is the little things. Adding other things that are more obvious doesn't change that.Your eagerness to declare me wrong has you consistently missing my point and arguing lovely straw-men. I find it particularly amusing that you call my DC 4 a "straw man." It isn't.

You have declared that the invisible wizard should make a stealth check. You later go on to make allowances for things like "well, maybe the perception is at disadvantage," but now you're ignoring the RAW to make up rules of your own, as well, so I will ignore those digressions and caveats.

A wizard is not known for having proficiency in Stealth, nor necessarily even a good Dex (though many have at least a positive modifier).

A result of a 4 on his stealth check is not unreasonable. Because you insist he must make one, it is plausible, even.

Another of your house rules you inject, despite decrying anybody else's suggestions as "ignoring the RAW," is to have the wizard use "passive stealth." The RAW don't support such a thing, but we can extrapolate what it would be: the result would be roughly an 11. Most parties will have at least one person in them with passive perception of 12+. So what you're really saying, here, is that it is no harder to detect the invisible wizard, to within 5 feet, than it is a visible wizard to within 5 feet.


The object incapable of taking actions displaces space. Dust will settle on the ground around it but not under it. Characters will see the difference. The object incapable of taking actions also does not breath and allow for hearing it. The invisibility spell can't actually be cast on an object, for that matter. It's cast on a creature per that description.This one is where you miss my point so grossly that I know it's my fault for being unclear.

Let me try to make it anew.

Would you automatically tell the party, upon entering a room, that they see a coin on the floor near the leg of a table? Or would you require them to roll Perception to notice it?

Would you give that Perception roll a DC of more than 11?


Is there any detail or object which might be worth noting in a room that, just by virtue of it being a fairly innocuous object sitting immobile in a room, you would assign a Perception DC greater than 11 to spot?


Note: I am not speaking of invisible objects, here.


But let's play with your invisible object and your justifications for it being noted via sight. The dust being displaced, or what-have-you.

What DC would you give that invisible object to be perceived? It cannot hide. The caster of invisibility took no effort other than casting invisibility on it. Are you going to say that it is as easy to spot as if it weren't invisible? Easier? Harder? By how much?




If you assign a Perception DC higher than the "passive stealth" of a wizard with a 0 dex (literally incapable of moving) to notice visible objects in a room which have not been deliberately hidden (thus nobody rolled stealth by proxy for them), and the wizard being invisible (or the object being invisible) does nothing to make it harder to see, then you've either discovered a hole in the RAW...or your interpretation is bad because it CREATES one where none need exist.

My claim is that what you are attempting to perceive is no longer "the invisible creature" when you're looking for visual cues that are not the creature's visible form, but instead you are attempting to perceive much higher-DC-to-detect visual effects, such as displacement of dust or a slight crushing of the carpet where he's standing. Similarly, the sound of a creature breathing, particularly to the point of pinpointing a 5-foot square of origin, is higher than the DC to perceive a creature standing where that creature is breathing.

[georgie_leech]

I think it's worth noting that casting Invisibility in combat is a different beast entirely; you're not going to stop paying attention to someone and where you're pretty sure they are just because they suddenly turned transparent. Most of these hypothetical deal with noticing an invisible something or other that isn't deliberately hidden but also isn't currently known to the party/npc/whatever. Just to head off the actions in combat thing.

[Segev]

I can't be the only one who is now considering having the PCs in a room where they intermittently hear the pages of a book turning and can't see where it came from. It is just too good of paranoia fodder to pass up!

Better still, have different DCs. The lower one just hears "paper rustling." Higher ones let them recognize it as "pages turning."

[Ashrym]

snip

Perhaps you should simply read the relevant DMG section I quoted and add bold to the relevant part. The party automatically detects the other person if that person isn't taking steps to be stealthy as soon as that person comes into range of vision or sound. The party does not need to see the invisible wizard for him to come within range of sound and he is automatically detected if he isn't trying to be stealthy. If he's trying to be stealthy then he uses a stealth check.

You spent so much time trying to create a custom scenario to prove me wrong based on circumstances that you still completely missed the RAW.

[georgie_leech]

Perhaps you should simply read the relevant DMG section I quoted and add bold to the relevant part. The party automatically detects the other person if that person isn't taking steps to be stealthy as soon as that person comes into range of vision or sound. The party does not need to see the invisible wizard for him to come within range of sound and he is automatically detected if he isn't trying to be stealthy. If he's trying to be stealthy then he uses a stealth check.

You spent so much time trying to create a custom scenario to prove me wrong based on circumstances that you still completely missed the RAW.

The question is whether that means 'aware of the existence of the wizard,' or 'can determine where the Wizard is to a degree of precision that allows weapon attacks.'

[MaxWilson]

Better still, have different DCs. The lower one just hears "paper rustling." Higher ones let them recognize it as "pages turning."

And if they roll poorly, they hear "claws scratching" or "knives sharpening"!

[RickAllison]

And if they roll poorly, they hear "claws scratching" or "knives sharpening"!

You say it sarcastically, but it would make it much more interesting!

[CantigThimble]

You say it sarcastically, but it would make it much more interesting!

I wouldn't be that specific (especially if the player knows they rolled low) but mentioning the sound of something scratching or ripping is a great idea.

Also I can totally imagine an introverted wizard at a party, coffeeshop, library or something just turning invisible while he reads so no one will bother him.

[MaxWilson]

You say it sarcastically, but it would make it much more interesting!

I wasn't sure if blue was the right color for "light-hearted, flippant-but-not-sarcastic" tone. I decided to leave it blue because if there was anyone who objected I didn't want it to turn into some kind of rules debate where they quote RAW to "prove" that it wouldn't be misheard like that at all.

[Vogonjeltz]

Believe it or not, identifying the "square" something is in by the sounds it makes is actually very hard. It's doable, but it's not trivial. A friend of mine in college was part of a group that designed a chamber for testing this, in fact. Aim at the right region, and you "hit" (no "disadvantage" or the like). But all you had was sound, not vision, to aim with.

Finding the right 5 foot square is easy, hitting something in 5 foot square is what is hard. And that's reflected by the character having disadvantage.

And I'd caution against relying purely on anecdotes as data:

"Humans can locate the source of a sound with extreme precision (within 2 degrees of space)!"
http://knowingneurons.com/2013/03/15/how-does-the-brain-locate-sound-sources/


...and in humans it doesn't have the kind of resolution or update frequency require for what's discussed in this thread. You can test this simply: Get a boffer, wiffle bat, or baguette (or other safe bopping implement of your choice), a friend and a blindfold and head to the nearest gymnasium or field. Blind fold yourself then call for your friend to approach you at a distance, and just casually jog around around the area in a random fashion making no real effort to be sneaky... just jogging around.

Then try to hit them with your wiffle bat, boffer or baguette while they move around. You will not hit them. You will not come close to hitting them. You'll be lucky not to trip and fall on your face.

Then try it with them ringing a cowbell, or singing your national anthemn at the top of their lungs. You'll get closer but still not ever hit them.

Record your results! You'll see that for an ordinary every day joe human hearing is not a precise enough sense to even come close to hitting their 5' square, let along actually targeting their body.

One could argue that D&D characters are better than the average joe human, but now we're back to them having sonar rather than ordinary human hearing. Which is fine if that's how capable you like your fantasy humans to be.

Yes, it's more difficult to hit a target you can't also see, that's why there's disadvantage on such attack rolls.


I can't be the only one who is now considering having the PCs in a room where they intermittently hear the pages of a book turning and can't see where it came from. It is just too good of paranoia fodder to pass up!

If the book is also invisible...how is the invisible person reading it?


Wow...just...wow. you seriously think you can pinpoint the exact location of someone over a mile away? Forget invisibility, I live in clear view of a suburbs area up the mountain just barely over a mile away. An above average person, about 6'5" is between 1.5mm and 2mm tall and less than 1mm wide from that distance visually. You may be able to faintly hear what sounds like it might be a voice if they are as loud as can be and there is absolutely zero interference (aka trees, animal sounds, a shrubbery, wind, creaky old house noise, ambient noise) but you would only be able to tell the general direction it came from and may not even notice the pin point of the person. To say you can instantly locate the exact position of someone invisible at that distance....that's like saying if you stand in the center of the field in Yankee Stadium and there is a clear thumbtack stuck to the back of one of the seats up in the bloody nose section with an iPod playing through headphones in the seat that you would be able to point directly at the thumbtack and know exactly what it is.
Or you think it works like the scene in Hotel Transylvania where the werewolf daughter sniffs the guys scent in the woods and knows instantly what seat he is in while aboard an airplane miles away...

The reason you can't see an infinite distance effectively is because there are obstructions and the earth curves.
http://www.livescience.com/33895-human-eye.html

So, with 0 obstructions and no curvature, you could hypothetically see light years. Specifically, 2.6 million light-years.

On earth the curvature is 3.1 miles. So anything on an Earth-sized planet that distance away could be visible as long as there's no obstruction in the intervening space.

From the last paragraph:

"Human-scale objects are resolvable as extended objects from a distance of just under 2 miles (3 km). For example, at that distance, we would just be able to make out two distinct headlights on a car."

Humans perceive sound at 3dB. For every distance doubling from the source sound decreases by 6 dB
http://www.nonoise.org/library/sndbasic/sndbasic.htm#5

A whisper is ~20dB, so it can be heard as far as ~4 feet away.
Conversational Speech is ~70dB, so it can be heard as far as ~2048 feet, or upwards of 1/2 a mile.
The loudest verified human shout (Jill Drake) was 129 dB which would theoretically be audible out to a fairly astounding 2,097,152 feet, or ~397 miles.

Bear in mind, that's with no background noise. To be truly audible we want to be ~10dB above background noise. If this were the woods, that would probably be around 30dB. So Jill's shout could be heard around 65,536 feet away or 12 miles in the woods before the sound has attenuated enough to be inaudible vs other louder noises.

[RickAllison]

Maybe the wizard has truesight or See Invisibility?

[MaxWilson]

"Humans can locate the source of a sound with extreme precision (within 2 degrees of space)!"
http://knowingneurons.com/2013/03/15/how-does-the-brain-locate-sound-sources/

If you actually check the literature (https://www.waisman.wisc.edu/bhl/about_publications/1994LitovskyMacmillanJAcoustSocAm.pdf), what you'll find is that that actually means is that (college students and middle-class author) humans are pretty good (2 degrees MMA) at distinguishing whether something straight ahead of them is moving from straight ahead to the left or right, but absolute rubbish (20-45 degrees MMA) at detecting whether something is moving to the center from the left or the right. MMA = Minimum audible angle, how big the gap has to be before the human can reliably tell the difference.

So a human looking straight at a noisy invisible target could tell with a high degree of accuracy whether it was moving to the left or the right--but if it's not straight ahead, it's hard for him to tell where it is.

Lesson: don't cite pop sci articles. :)

[Vogonjeltz]

If you actually check the literature (https://www.waisman.wisc.edu/bhl/about_publications/1994LitovskyMacmillanJAcoustSocAm.pdf), what you'll find is that that actually means is that (college students and middle-class author) humans are pretty good (2 degrees MMA) at distinguishing whether something straight ahead of them is moving from straight ahead to the left or right, but absolute rubbish (20-45 degrees MMA) at detecting whether something is moving to the center from the left or the right. MMA = Minimum audible angle, how big the gap has to be before the human can reliably tell the difference.

So a human looking straight at a noisy invisible target could tell with a high degree of accuracy whether it was moving to the left or the right--but if it's not straight ahead, it's hard for him to tell where it is.

Lesson: don't cite pop sci articles. :)

Max, a couple things.

First, you mixed that up, lag is when it starts middle and goes right or left, and lead is when it starts on a side and goes middle. The averages collected suggest a slight superiority for lead MAA vis lag MMA.

And by slight I mean 5 degrees difference between the two types for the mean of the group.

It's worth noting here that the group was only 4 subjects, and 2 of those subjects had some pretty crazy difference between the two: JPR had .93 degree average MMA for lead and an astoundingly bad almost 10 degree average for lag, which was 3 points higher than the next closest person.

In comparison, NAM was averaging 1 degree lead and 2.59 degrees lag.

The massive performance variance between the two suggests more test subjects are needed to accurately establish anything meaningful.

All that being said, this doesn't even establish localization, it establishes the ability to detect sound motion. (Cue sound moves to end sound). I'd also note the decibels are even lower than a whisper, so that's pretty unusual, something the authors of the study note themselves.

It was interesting, but the conclusions (around 2 degrees arc) still reinforce the pages I linked.

[Ashrym]

The question is whether that means 'aware of the existence of the wizard,' or 'can determine where the Wizard is to a degree of precision that allows weapon attacks.'

It's a better question, but 5e simplified that with advantage and things like noticing visual clues (like footprints) once those are within visible range. The rules were designed for simplicity and it's pretty easy to keep it simple and state that the wizard was trying to be stealthy while reading his book invisibly; why else turn invisible to do it? Then it's his stealth check where he's actually trying to be quiet and not disturb his surroundings so it becomes easy to compare his stealth to passive perception.

The arguments were all about over-complicating the situation and claim the rules did not apply. DM's always have prerogative to adjust based on circumstances etc but the basic rules are there either way.

[MaxWilson]

Max, a couple things.

First, you mixed that up, lag is when it starts middle and goes right or left, and lead is when it starts on a side and goes middle. The averages collected suggest a slight superiority for lead MAA vis lag MMA.

You're right, I mixed up the lag and lead. Whoops!

On point, though, in the experiment that most resembles the scenario we're discussing in this thread (zero azimuth, no standard), lead MMA is 1.74 degrees and lag MMA is 17.17, a vast superiority for lead MMA. You're looking at the column that includes a standard reference signal (an initial signal from a known location, which apparently helps people get oriented), but in the no-standard case, lag is uniformly bad compared to lead. E.g. NAM does 1.55 on lead but 20.77 on lag.

So in the case we actually care about, there are no crazy differences, and nobody gets close to two degrees for lag signals even though lead is apparently pretty easy for them. (I have no idea why lead is easier.)


The massive performance variance between the two suggests more test subjects are needed to accurately establish anything meaningful.

I'll go with that--but that leaves that claim about "humans can locate sound to within two degrees" unsupported. Rather, "one experiment suggests that under certain conditions, some humans can discriminate between certain sounds separated by two degrees." Pretty big difference there.


All that being said, this doesn't even establish localization, it establishes the ability to detect sound motion. (Cue sound moves to end sound). I'd also note the decibels are even lower than a whisper, so that's pretty unusual, something the authors of the study note themselves.

Yep. And localization is much harder than discrimination or sound motion. But then...


It was interesting, but the conclusions (around 2 degrees arc) still reinforce the pages I linked.

Huh?!? At this point you've lost me. If anything it's a 17 degree arc. But it's not even that, because as we just discussed, sound motion detection/discrimination is not localization.

Uneducated layman that I am, I cannot find any reason to believe that humans can easily localize sounds (especially distant sounds!) to within 2 degrees. The experimental results cast doubt on that claim picture, and so do my lived experiences. I don't think the blindfolded shooting experiment is going to result in many hits.

[Vogonjeltz]

You're right, I mixed up the lag and lead. Whoops!

On point, though, in the experiment that most resembles the scenario we're discussing in this thread (zero azimuth, no standard), lead MMA is 1.74 degrees and lag MMA is 17.17, a vast superiority for lead MMA. You're looking at the column that includes a standard reference signal (an initial signal from a known location, which apparently helps people get oriented), but in the no-standard case, lag is uniformly bad compared to lead. E.g. NAM does 1.55 on lead but 20.77 on lag.

So in the case we actually care about, there are no crazy differences, and nobody gets close to two degrees for lag signals even though lead is apparently pretty easy for them. (I have no idea why lead is easier.)



I'll go with that--but that leaves that claim about "humans can locate sound to within two degrees" unsupported. Rather, "one experiment suggests that under certain conditions, some humans can discriminate between certain sounds separated by two degrees." Pretty big difference there.



Yep. And localization is much harder than discrimination or sound motion. But then...



Huh?!? At this point you've lost me. If anything it's a 17 degree arc. But it's not even that, because as we just discussed, sound motion detection/discrimination is not localization.

Uneducated layman that I am, I cannot find any reason to believe that humans can easily localize sounds (especially distant sounds!) to within 2 degrees. The experimental results cast doubt on that claim picture, and so do my lived experiences. I don't think the blindfolded shooting experiment is going to result in many hits.

Yes, but, and this is the key, characters are assumed to always be in motion by the rules, actively trying to defend themselves. As such, there's no reason to assume the character wouldn't have heads on a swivel as it were, constantly looking around giving them an effective 1 degree of accuracy in all directions, pinpoint accuracy!

[MaxWilson]

Yes, but, and this is the key, characters are assumed to always be in motion by the rules, actively trying to defend themselves. As such, there's no reason to assume the character wouldn't have heads on a swivel as it were, constantly looking around giving them an effective 1 degree of accuracy in all directions, pinpoint accuracy!

Was this supposed to be in blue text? Poe's Law and all that.

Constant movement and the lack of a fixed direction (per the experimental design) is going to make your accuracy worse, not better.

[Vogonjeltz]

Was this supposed to be in blue text? Poe's Law and all that.

Constant movement and the lack of a fixed direction (per the experimental design) is going to make your accuracy worse, not better.

Triangulation would arguably result and that doesn't make you worse at locating a thing. 🤔

[MaxWilson]

Triangulation would arguably result and that doesn't make you worse at locating a thing. 🤔

For nearby creatures, yes. For creatures a mile or more away, not likely, and not with the precision required to locate a 5' square.

In short, it depends. Are we still talking about Accidentally Invisible Loud Guy?

[IShouldntBehere]

Yes, it's more difficult to hit a target you can't also see, that's why there's disadvantage on such attack rolls.




No I mean you won't even come close to bringing the weapon towards them. You'll be targeting the entirely wrong space by wide margins. You will not be attacking the same 5' square they're standing in, let alone anything that could be considered the approximate space they're body was occupying.

It's fine to say that humans have Sonar in D&D that give them this kind of accuracy based on sound it's a legit way to reconcile a particular view of RAW with what we know about humans. However it's just not consistent to say that (D&D Human hearing as we do && that means they can pick out individuals with sufficient precision to target them && disadvantage presents a reasonable model of the loss in precision from sighted targeting).

We can say: D&D humans have much better hearing than ordianry , "Sonar" as I've been putting it. That works. D&D Characters are special heroes.
We can say: we don't really care about accurately modeling hearing and let's just ignore the the whole issue for the sake of having a game to run as game. That works. The game is the game, we can have fun with it that way if want.
We can say: OK, We need some mechanic other than disadvantage such having to guess what square something is in, or making perception checks too resolve the space something is in. That works. It fits within the general framework of the 5e rules.

What I don't think one can really honestly and accurately claim is that a normally sighted human suddenly deprived of sight, can consistently get an attack within 5' of a target they can't see that is only making baseline levels of noise like the sound of simply jogging along. Hence the test I put forward to you.

If in that test you are generally targeting your friend accurately but failing to connect, than you're facing something like disadvantage on attack rolls as an ordinary joe human.
If in that test you are missing by a mile, and only with luck scraping the edges of his "Space", than you're facing something greatly unlike disadvantage on attack rolls as an ordinary joe human.


Try the test and fail it and you'll see this means either we want the rules to model ordinary human hearing and thus not allow precision targeting by default of unseen targets, OR we want to accept that D&D humans are special that they have "Sonar" of sort.


EDIT: OR One can claim (as I like to do), that an Invisible character simply isn't truly Invisible. They've got predator cloaking, mostly transparent but telltale signs that are really easy to see if you know to be looking for them. A great tool for sneaking around folks who aren't already tracking your position, awesome at breaking up your outline in combat and generally being nice for camo but worthless at concealing your exact position against an alert target.

[Cybren]

We can say: D&D humans have much better hearing than ordianry , "Sonar" as I've been putting it. That works. D&D Characters are special heroes.
We can say: we don't really care about accurately modeling hearing and let's just ignore the the whole issue for the sake of having a game to run as game. That works. The game is the game, we can have fun with it that way if want.
We can say: OK, We need some mechanic other than disadvantage such having to guess what square something is in, or making perception checks too resolve the space something is in. That works. It fits within the general framework of the 5e rules.


This is making the mistake of rationalizing what is a gameplay conceit(players should have some method of attacking creatures they know exist but can't see) as a diagetic one (creatures in this world, all of them, not just humans, anything that can make attack rolls and doesn't have a blindsight-esque ability)



EDIT: OR One can claim (as I like to do), that an Invisible character simply isn't truly Invisible. They've got predator cloaking, mostly transparent but telltale signs that are really easy to see if you know to be looking for them. A great tool for sneaking around folks who aren't already tracking your position, awesome at breaking up your outline in combat and generally being nice for camo but worthless at concealing your exact position against an alert target.

EDIT myself: invisible creatures are invisible. They are most certainly not perceivable by vision. Elsewise the ability would be described as "transparency". There are weird gameplay occurrences that happen when you take rules mostly structured around skirmishes between small numbers of combatants in small to medium sized, usually enclosed spaces, and try to apply them mechanistically to the entire world. I'd rather just fall back on let the DM make a quick ruling, and if it is reasonable and everyone is happy with it, move on. Elsewise we get GURPS, which is great, to be fair, but also rightly criticized for having all sorts of rules minutia it can track.

[Segev]

I wouldn't be that specific (especially if the player knows they rolled low) but mentioning the sound of something scratching or ripping is a great idea.

Also I can totally imagine an introverted wizard at a party, coffeeshop, library or something just turning invisible while he reads so no one will bother him.
That raises an interesting question: assuming the book is also invisible (so nobody sees a book spontaneously turning its own pages), can the wizard see it to read it? Or would he need see invisible active simultaneously with invisibility to pull this off?



Perhaps you should simply read the relevant DMG section I quoted and add bold to the relevant part. The party automatically detects the other person if that person isn't taking steps to be stealthy as soon as that person comes into range of vision or sound. The party does not need to see the invisible wizard for him to come within range of sound and he is automatically detected if he isn't trying to be stealthy. If he's trying to be stealthy then he uses a stealth check.

You spent so much time trying to create a custom scenario to prove me wrong based on circumstances that you still completely missed the RAW.
Alright.

So, the RAW, as you read it, says that creatures, no matter their size nor visibility, who are not making a stealth check are automatically noticed. Even if objects, which never make stealth checks, might require perception rolls to be noticed.

So a fly on a wall that is not making any special effort to hide is automatically noticed, but a coin on a floor might require a DC 15 or 20 perception check to notice it.

I'm willing to grant that a rigorous reading of the RAW might lead to that conclusion, especially since 5e is all about ignoring rigorous readings of the RAW when they don't make sense. But I'm curious, because you still haven't answered me:

Is it any harder to notice a coin on the floor that's invisible than it is to notice a coin on the floor that's visible? What about a fly on a wall?

If your answer is, essentially, "No, invisibility actually does nothing to make it harder to notice anything other than allowing somebody to make a stealth check," I'll accept that you can probably find justification in the RAW for it. After all, the RAW Charmed condition is nearly useless, as well, and makes many of the effects that reference it (because they seem to think it does more than it says it does) similarly useless (see: geas). But I want to be sure that you're arguing that the RAW is stupid, and realize just how stupid the RAW is if that's the only way to interpret it.


The question is whether that means 'aware of the existence of the wizard,' or 'can determine where the Wizard is to a degree of precision that allows weapon attacks.'This would seem to be the more pertinent question to answer per the opening post's discussion.

I would argue no. At best, you can say that you get a telltale sound or something.

Though part of my issue here is that if all invisibility does is let you make a stealth check, that means the invisible wizard is still practically unable to go undetected. After all, he probably doesn't have a very good stealth check. And invisibility in 5e lacks any listed bonuses to such checks (unlike 3.PF, where it came with a massive bonus).


Finding the right 5 foot square is easy, hitting something in 5 foot square is what is hard. And that's reflected by the character having disadvantage.

And I'd caution against relying purely on anecdotes as data:

"Humans can locate the source of a sound with extreme precision (within 2 degrees of space)!"
http://knowingneurons.com/2013/03/15/how-does-the-brain-locate-sound-sources/.Cute, dismissing my colleague's actual masters work, done with data collection techniques and documentation, as "anecdotal" while quoting a popular science news article as if it were rigorous science dutifully reported.

I'll leave the discussion of the specific flaws in your counterexample to others, who've thoroughly dismantled it. But seriously, dismissing research projects as "anecdotal" is essentially admitting you're just arguing to "prove" yourself right, regardless of whether you are or not. Either that, or a tacit admission that you didn't actually read what was said.



For the record, I participated as one of the (many) subjects in (many) groups who engaged in that project. It was actually fun; essentially you had a light-gun like device and were in a dark room, and noises would occur. You're in teams of 4, and each of the 4 of you had one particular sound for which you were listening. You were to shoot at it every time you heard it.

While they weren't testing for "5 foot squares," the accuracy was only required to roughly that precision to determine if you hit or not. And the "sounds" weren't dodging. They were audible equivalents of pop-up targets that are in pace for a specified amount of time. Missing was largely due to aiming in the wrong place entirely.


No melee variations occurred, largely due to being unable to really achieve them. I will note that DISTANCE was not part of the test, and that it probably would have been a lot harder to accurately judge distance to the sound source if you had to run up to it before you could swing at the seemingly empty space. D&D 3e was already awfully generous in allowing a Listen check with a penalty to identify the correct 5-ft. square.

[CantigThimble]

That raises an interesting question: assuming the book is also invisible (so nobody sees a book spontaneously turning its own pages), can the wizard see it to read it? Or would he need see invisible active simultaneously with invisibility to pull this off?

Hrmm, for the sake of simplicity I would probably rule that invisible people can see themselves or by some arcane means can percieve themselves. There are a lot of actions invisible characters are expected to be able to do that would be quite a bit harder if they couldn't see their own belongings.

[Segev]

Hrmm, for the sake of simplicity I would probably rule that invisible people can see themselves or by some arcane means can percieve themselves. There are a lot of actions invisible characters are expected to be able to do that would be quite a bit harder if they couldn't see their own belongings.

True; down that path of RAW pedantry lies the question of whether you have to beat your own Stealth roll to Perceive yourself, too. :smallbiggrin:

[georgie_leech]

True; down that path of RAW pedantry lies the question of whether you have to beat your own Stealth roll to Perceive yourself, too. :smallbiggrin:

And now I'm imagining the Quest of the legendary Sneakius Quietus, Rogue/Monk, who set off on a journey to find himself. Not to discover who he is, he just lost track of himself after a particularly good Hide check 3 years ago and hasn't been able to figure out where he is since.

[Segev]

And now I'm imagining the Quest of the legendary Sneakius Quietus, Rogue/Monk, who set off on a journey to find himself. Not to discover who he is, he just lost track of himself after a particularly good Hide check 3 years ago and hasn't been able to figure out where he is since.

You misspelled "Waldo." :smallwink:

[RSP]

2 things:

1) I'd imagine anything that turns invisible because it is now held by an invisible character (i.e. the book), would be visible to the invisible character.

2) I posted it much earlier in this thread, but as it seems to have been ignored, here is the RAW of hiding as it's written in the rules:

"The DM decides when circumstances are appropriate for hiding. When you try to hide, make a Dexterity (Stealth) check."

I added that second sentence this time to emphasis that the first rule of hiding is that the DM decides when there is a chance someone is hiding, and that this occurs before any characters decide to hide or not.

So, using all these examples; the fly on the wall, or the invisible reader, etc; the DM, per RAW, decides if this is a circumstance that is appropriate for hiding. If the DM decides it is indeed one such circumstance then it doesn't matter whether or not the character decides to actively hide or not, the DM has already determined a stealth roll is required. Roll the stealth vs passive perception and move on.

[MaxWilson]

That raises an interesting question: assuming the book is also invisible (so nobody sees a book spontaneously turning its own pages), can the wizard see it to read it? Or would he need see invisible active simultaneously with invisibility to pull this off?

The latter, or else it is an invisible braille book. :)

BTW, I'm very interested in reading your friend's master's thesis, if a link is available.

[krugaan]

For the record, I participated as one of the (many) subjects in (many) groups who engaged in that project. It was actually fun; essentially you had a light-gun like device and were in a dark room, and noises would occur. You're in teams of 4, and each of the 4 of you had one particular sound for which you were listening. You were to shoot at it every time you heard it.

While they weren't testing for "5 foot squares," the accuracy was only required to roughly that precision to determine if you hit or not. And the "sounds" weren't dodging. They were audible equivalents of pop-up targets that are in pace for a specified amount of time. Missing was largely due to aiming in the wrong place entirely.


No melee variations occurred, largely due to being unable to really achieve them. I will note that DISTANCE was not part of the test, and that it probably would have been a lot harder to accurately judge distance to the sound source if you had to run up to it before you could swing at the seemingly empty space. D&D 3e was already awfully generous in allowing a Listen check with a penalty to identify the correct 5-ft. square.

That's pretty interesting, laser tag as science!

Still, the purpose of that experiment was likely to isolate hearing as the only means of detection. In "real life", there would be other clues that would hint as to the location of an invisible person... a whiff of sweat, rattle of gravel, etc.

Although one might argue that's the point of the perception check.

[georgie_leech]

That's pretty interesting, laser tag as science!

Still, the purpose of that experiment was likely to isolate hearing as the only means of detection. In "real life", there would be other clues that would hint as to the location of an invisible person... a whiff of sweat, rattle of gravel, etc.

Although one might argue that's the point of the perception check.

Mind you, those are either other sources of sound or the even less helpful smell. Humans might have some degree of skill with discriminating between different scents, and figuring out if the smell is getting stronger or weaker, but it has none of the dire ti on our ears have. We can't tell based on smell alone whether something is to the right or left of us, partially because of how air flows through our nose in the first place. So scent seems like the kind of thing you can use to detect the presence of something, but it's really not the kind of thing we can use to pinpoint location.

[krugaan]

Mind you, those are either other sources of sound or the even less helpful smell. Humans might have some degree of skill with discriminating between different scents, and figuring out if the smell is getting stronger or weaker, but it has none of the dire ti on our ears have. We can't tell based on smell alone whether something is to the right or left of us, partially because of how air flows through our nose in the first place. So scent seems like the kind of thing you can use to detect the presence of something, but it's really not the kind of thing we can use to pinpoint location.

I also meant things like an invisible person kicking up small dust clouds, disturbing foliage, rocks, whatever, distorting the sound of dripping water. Yeah, the smell thing is a little farfetched when taken by itself, but my point was that perception is the sum of your senses, and losing one sense is not remotely the same as losing all BUT one.

Although, again... That might be appropriate thematically for a perception check (natch).

Then again, it might be obvious enough that a hyper alert person in combat might pick up on it anyway, unless the invisible target were taking pains to mask those giveaways... Which would be a hide action.

[MaxWilson]

Mind you, those are either other sources of sound or the even less helpful smell. Humans might have some degree of skill with discriminating between different scents, and figuring out if the smell is getting stronger or weaker, but it has none of the dire ti on our ears have. We can't tell based on smell alone whether something is to the right or left of us, partially because of how air flows through our nose in the first place. So scent seems like the kind of thing you can use to detect the presence of something, but it's really not the kind of thing we can use to pinpoint location.

As an aside, 5E's writers really should make more use of smell. From an adventure-writer's perspective, smell is ideal: it helps "trigger the scene" by foreshadowing that now you're in a potential danger zone, but it doesn't reveal exact locations (which would short-circuit play, perhaps straight to combat) or the exact identity of the threat(?).

It would have been awesome if every MM entry had a "spoor" entry that lists three or four subtle signals as to what kind of challenge players are dealing with in this location. E.g. "stench of rotten meat mixed with formaldehyde" could be one of the four entries for trolls, "smell of pine cones and fresh rain" for Couatls, "orange citrus and sulfur" for death knights, "an enormous horse" for gryphons. The hope is that when players beat that Perception check and smell formaldehyde, they can put that together with the suspicious lack of elm trees in the vicinity (trolls love the taste of elm trees) and shout "Trolls!" and break out the flaming oil. Or at least, when they get jumped by a band of ten trolls they won't complain to the DM because they'll realize in retrospect that the trolls must have been there all along.

[krugaan]

As an aside, 5E's writers really should make more use of smell. From an adventure-writer's perspective, smell is ideal: it helps "trigger the scene" by foreshadowing that now you're in a potential danger zone, but it doesn't reveal exact locations (which would short-circuit play, perhaps straight to combat) or the exact identity of the threat(?).

It would have been awesome if every MM entry had a "spoor" entry that lists three or four subtle signals as to what kind of challenge players are dealing with in this location. E.g. "stench of rotten meat mixed with formaldehyde" could be one of the four entries for trolls, "smell of pine cones and fresh rain" for Couatls, "orange citrus and sulfur" for death knights, "an enormous horse" for gryphons. The hope is that when players beat that Perception check and smell formaldehyde, they can put that together with the suspicious lack of elm trees in the vicinity (trolls love the taste of elm trees) and shout "Trolls!" and break out the flaming oil. Or at least, when they get jumped by a band of ten trolls they won't complain to the DM because they'll realize in retrospect that the trolls must have been there all along.

That would be kind of neat, although I doubt they would spend the energy making a "Poop smells like..." category for every entry. Didn't old MM entries used to have things like diet / habitat / culture?

That might be more appropriate for a wiki-like monster manual, but those are nigh-impossible to monetize, and are pretty counter to the word-light focus in 5E.

[IShouldntBehere]

I also meant things like an invisible person kicking up small dust clouds, disturbing foliage, rocks, whatever, distorting the sound of dripping water. Yeah, the smell thing is a little farfetched when taken by itself, but my point was that perception is the sum of your senses, and losing one sense is not remotely the same as losing all BUT one.

Although, again... That might be appropriate thematically for a perception check (natch).

Then again, it might be obvious enough that a hyper alert person in combat might pick up on it anyway, unless the invisible target were taking pains to mask those giveaways... Which would be a hide action.

Which is fine if we consider all creatures everywhere to by hyper alert at all times regardless of circumstance. If you take the RAW to be the always know the location of invsisble things unless they're actively hiding to be true, then the following is also a thing that the rules totally say should happen:

Muntz, the feebleminded (INT, 3, WIS 4, CHA 5) is drunk off his keester, watching puppet show while a group of ragged streetch urchins are pulling on his tunic demanding money.

Stan, the casually invisible comes to the festival. He is invisible and walking at an ordinary pace, not being particularly deliberate about being stealthy but not going out of his way to make noise or anything. He's just walking normally like anyone would down the street at a festival. Stan has made FATAL ERROR, for you see. Stan has passed several women without saying "Excuse me Ma'am", a minor social misstep normally but this MUNTZ. MUNTZ MINDS MANNERS.

Muntz is of course aware of the exact position of everyone in this scene, including our invisible Stan. Since he knows this and has heard no "Excuse me Ma'am" he is aware and ENRAGED by stans lack of class.

MUNTZ tips his brimmed hat up and cries "I'LL TEACH HIM SOME MANNERS M'LADY" and charges to Stans exact position (being sure to say excuse me as he passes through the crowd), as his long pony tail flows behind him. MUNTZ winds up for punch and connects directly!

Certainly I can buy hyper-aware people picking up that sort of thing. It just feels like it's the kind of thing that would be a specific ability, feat, class or racial feature. Rather than something that holds true for everyone, everywhere PC & NPC alike at all times no matter what.

[krugaan]

Which is fine if we consider all creatures everywhere to by hyper alert at all times regardless of circumstance. If you take the RAW to be the always know the location of invsisble things unless they're actively hiding to be true, then the following is also a thing that the rules totally say should happen:

Muntz, the feebleminded (INT, 3, WIS 4, CHA 5) is drunk off his keester, watching puppet show while a group of ragged streetch urchins are pulling on his tunic demanding money.

Stan, the casually invisible. Is invisible walking at an ordinary pace, not being particularly deliberate about being stealthy but not going out of his way to make noise or anything. He's just walking normally like anyone would down the street a festival. Stan has made FATAL ERROR, for you see. Stan has passed several women without saying "Excuse me Ma'am", a minor social misstep normally but this MUNTZ. MUNTZ MINDS MANNERS.

Muntz is of course aware of the exact position of everyone in this scene, including our invisible Stan. Since he knows this and has heard no "Excuse me Ma'am" he is aware and ENRAGED by stans lack of class.

MUNTZ tips his brimmed hat up and cries "I'LL TEACH HIM SOME MANNERS M'LADY" and charges to Stans exact position (being sure to say excuse me as he passes through the crowd), as his long pony tail flows behind him. MUNTZ winds up for punch and connects directly!

Certainly I can buy hyper-aware people picking up that sort of thing. It just feels like it's the kind of thing that would be a specific ability, feat, class or racial feature.

Again, if you follow that kind of rationale, you get notions like "unlimited range hearing and daylight vision" and "detect things at an unlimited range", which I think we can reasonably dismiss as absurd.

In short, until they release better guidelines (or even A guideline) on the general ranges for hearing and vision somewhere, it's all DM's discretion.

I'd also like to note that the full context of the quote is "hyper aware in combat", which is indeed RAW.

Also, if MUNTZ (why is this capitalized again?) is an leveled PC, he's probably learned the value of being generally alert, no matter how dumb he is, or he wouldn't be, well, a professional adventurer and still alive.

[CantigThimble]

Also, if MUNTZ (why is this capitalized again?) is an leveled PC, he's probably learned the value of being generally alert, no matter how dumb he is, or he wouldn't be, well, a professional adventurer and still alive.

In that case he might have proficiency or expertise in perception, possibly even the alert feat, bumping his passive perception up to the point where he would notice the existence of an invisible person who wasn't particularly stealthy despite his poor eyesight.

[krugaan]

In that case he might have proficiency or expertise in perception, possibly even the alert feat, bumping his passive perception up to the point where he would notice the existence of an invisible person who wasn't particularly stealthy despite his poor eyesight.

Two words...

BEER GOGGLES!

... grants advantage on perception checks.

#onlyIn5E #forumLogic

[IShouldntBehere]

Again, if you follow that kind of rationale, you get notions like "unlimited range hearing and daylight vision" and "detect things at an unlimited range", which I think we can reasonably dismiss as absurd.

In short, until they release better guidelines (or even A guideline) on the general ranges for hearing and vision somewhere, it's all DM's discretion.

I'd also like to note that the full context of the quote is "hyper aware in combat", which is indeed RAW.

Also, if MUNTZ (why is this capitalized again?) is an leveled PC, he's probably learned the value of being generally alert, no matter how dumb he is, or he wouldn't be, well, a professional adventurer and still alive.

Muntz is an NPC. But when MUNTZ does things or when MUNTZ SAYS THINGS it's in all caps because that's just how he rolls. We will say in this circumstance Stan was the PC. His character is extremely vain and lost a bet with another PC and had to walk around the festival for 5 minutes in a gaudy unattractive outfit. "But AH-HA though Stan. If I'm INVISIBLE nobody will actually see me in it". Which worked! Nobody saw him in it. However is lack of manners wound up getting him decked by Muntz and his MUNTZ PUNCH! (which is not nearly as bad an embarrassment as all those sequins, so still a win in his mind!)

[georgie_leech]

As an aside, 5E's writers really should make more use of smell. From an adventure-writer's perspective, smell is ideal: it helps "trigger the scene" by foreshadowing that now you're in a potential danger zone, but it doesn't reveal exact locations (which would short-circuit play, perhaps straight to combat) or the exact identity of the threat(?).

It would have been awesome if every MM entry had a "spoor" entry that lists three or four subtle signals as to what kind of challenge players are dealing with in this location. E.g. "stench of rotten meat mixed with formaldehyde" could be one of the four entries for trolls, "smell of pine cones and fresh rain" for Couatls, "orange citrus and sulfur" for death knights, "an enormous horse" for gryphons. The hope is that when players beat that Perception check and smell formaldehyde, they can put that together with the suspicious lack of elm trees in the vicinity (trolls love the taste of elm trees) and shout "Trolls!" and break out the flaming oil. Or at least, when they get jumped by a band of ten trolls they won't complain to the DM because they'll realize in retrospect that the trolls must have been there all along.

At least in some cases, definitely. Smell is a really under appreciated DM tool to give out vague clues.

[krugaan]

Muntz is an NPC. But when MUNTZ does things or when MUNTZ SAYS THINGS it's in all caps because that's just how he rolls. We will say in this circumstance Stan was the PC. His character is extremely vain and lost a bet with another PC and had to walk around the festival for 5 minutes in a gaudy unattractive outfit. "But AH-HA though Stan. If I'm INVISIBLE nobody will actually see me in it". Which worked! Nobody saw him in it. However is lack of manners wound up getting him decked by Muntz and his MUNTZ PUNCH! (which is not nearly as bad an embarrassment as all those sequins, so still a win in his mind!)

Hey!... bedazzling isn't a thing anymore?

On a side note, my half-orc champion fighter is named Gronk.

He calls GWM-ing "gronkification". Now everyone says "gronkify" to denote -5/+10.

On a more serious note, that sounds internally consistent, if a bit implausible.

[MaxWilson]

That would be kind of neat, although I doubt they would spend the energy making a "Poop smells like..." category for every entry. Didn't old MM entries used to have things like diet / habitat / culture?

That might be more appropriate for a wiki-like monster manual, but those are nigh-impossible to monetize, and are pretty counter to the word-light focus in 5E.

It doesn't have to be fecal waste specifically. "Spoor" encompasses any sign or trace of a thing's presence. Smell, tracks, presence or absence of certain animal sounds in the environment (no birds chirping), slime trails, etc. Variety is good.

And yes, old MM entries used to have entries for habitat/ecology/social organization/terrain/treasure type/etc. I steal lots of ideas from my 2nd edition Monster Manual + various Monstrous Compendia. Frog God's Fifth Edition Foes still has them in fact, which is one of the things that makes Fifth Edition Foes a better product than 5E's MM.

[Vogonjeltz]

For nearby creatures, yes. For creatures a mile or more away, not likely, and not with the precision required to locate a 5' square.

In short, it depends. Are we still talking about Accidentally Invisible Loud Guy?

Uhm, yes, fair enough, I don't think there's any means of engaging a creature a mile away however?

At most we're talking the range of a bow shot which is what, 600 feet ish, probably substantially less, more on the order of say 60 feet. considering one need only know the specific direction, 1 degree of accuracy is more than enough to line target the square (not taking into account possible physical obstructions along the way). Besides, they would have to be making enough noise to be audible (something with enough dB minus the background noise level minus 3 (to remain audible) divided by 6 which gives you the number of doublings beyond 1 foot that they would be.


No I mean you won't even come close to bringing the weapon towards them. You'll be targeting the entirely wrong space by wide margins. You will not be attacking the same 5' square they're standing in, let alone anything that could be considered the approximate space they're body was occupying.

It's fine to say that humans have Sonar in D&D that give them this kind of accuracy based on sound it's a legit way to reconcile a particular view of RAW with what we know about humans. However it's just not consistent to say that (D&D Human hearing as we do && that means they can pick out individuals with sufficient precision to target them && disadvantage presents a reasonable model of the loss in precision from sighted targeting).

We can say: D&D humans have much better hearing than ordianry , "Sonar" as I've been putting it. That works. D&D Characters are special heroes.
We can say: we don't really care about accurately modeling hearing and let's just ignore the the whole issue for the sake of having a game to run as game. That works. The game is the game, we can have fun with it that way if want.
We can say: OK, We need some mechanic other than disadvantage such having to guess what square something is in, or making perception checks too resolve the space something is in. That works. It fits within the general framework of the 5e rules.

What I don't think one can really honestly and accurately claim is that a normally sighted human suddenly deprived of sight, can consistently get an attack within 5' of a target they can't see that is only making baseline levels of noise like the sound of simply jogging along. Hence the test I put forward to you.

If in that test you are generally targeting your friend accurately but failing to connect, than you're facing something like disadvantage on attack rolls as an ordinary joe human.
If in that test you are missing by a mile, and only with luck scraping the edges of his "Space", than you're facing something greatly unlike disadvantage on attack rolls as an ordinary joe human.


Try the test and fail it and you'll see this means either we want the rules to model ordinary human hearing and thus not allow precision targeting by default of unseen targets, OR we want to accept that D&D humans are special that they have "Sonar" of sort.


EDIT: OR One can claim (as I like to do), that an Invisible character simply isn't truly Invisible. They've got predator cloaking, mostly transparent but telltale signs that are really easy to see if you know to be looking for them. A great tool for sneaking around folks who aren't already tracking your position, awesome at breaking up your outline in combat and generally being nice for camo but worthless at concealing your exact position against an alert target.

The literature (including the one linked by Max) is clear that humans (when able to face the source of the sound, I'll caveat that) can localize with high precision.

The ability to know the sound is coming from space X with certainty in no way translates to the hand-ear coordination required to aim at the sound or to actually hit it. But that's literally what disadvantage is modeling in a low level way. i.e. It's harder.

Anyway, I just did a totally unscientific experiment with a friend where I closed my eyes in a large room, stuck my fingers in my ears and hummed loudly while they chose a position. I think removed my hands from my ears, had them say one word and I would point to the sound. Turns out they were ~30 feet away to my left, I pointed and was off by about 1 foot from their actual position.

Now that's just one sound, not many sounds as would be occurring in combat, repeatedly, and I was not even facing them as I inevitably would have turned to reconfirm before (in a game) making the attack. So, anecdotally I tried the test you mentioned and it was effectively succesful as 1 foot variance is well within the 5 foot square.

Here's the thing, I don't find this outcome surprising at all because I play FPS games where the sounds made by opponents (and the direction that sound is coming from) are mind-bogglingly crucial to outperforming opponents. Identifying sounds appropriately (enemy fire vs friendly) and location (footsteps, scraping on rock, reloading, breathing, whatever) without actually seeing them (sometimes they're behind you) and while a number of competing and extremely loud (gunfire, explosions) sounds are occuring often mean the difference between victory and defeat.

That being said, I have a hypothesis I think would be worth looking into which I'll detail after the response to Segev's post.

I'm not in favor of Invisibility being construed as functioning like Predator (although I don't mind the imagery, it doesn't fall in line with what the spell suggests which is functioning as the invisibility cloak in Harry Potter, for example).


Cute, dismissing my colleague's actual masters work, done with data collection techniques and documentation, as "anecdotal" while quoting a popular science news article as if it were rigorous science dutifully reported.

I'll leave the discussion of the specific flaws in your counterexample to others, who've thoroughly dismantled it. But seriously, dismissing research projects as "anecdotal" is essentially admitting you're just arguing to "prove" yourself right, regardless of whether you are or not. Either that, or a tacit admission that you didn't actually read what was said.



For the record, I participated as one of the (many) subjects in (many) groups who engaged in that project. It was actually fun; essentially you had a light-gun like device and were in a dark room, and noises would occur. You're in teams of 4, and each of the 4 of you had one particular sound for which you were listening. You were to shoot at it every time you heard it.

While they weren't testing for "5 foot squares," the accuracy was only required to roughly that precision to determine if you hit or not. And the "sounds" weren't dodging. They were audible equivalents of pop-up targets that are in pace for a specified amount of time. Missing was largely due to aiming in the wrong place entirely.


No melee variations occurred, largely due to being unable to really achieve them. I will note that DISTANCE was not part of the test, and that it probably would have been a lot harder to accurately judge distance to the sound source if you had to run up to it before you could swing at the seemingly empty space. D&D 3e was already awfully generous in allowing a Listen check with a penalty to identify the correct 5-ft. square.

4 participants with the amount of variation listed (and the lack of separation by gender) do not provide statistical significance. That is why I called it anecdotal data, it's little better than me performing the test suggested by IShouldntBehere above, and the wide variation amongst the participants (1 female, 2 males of a similar age, 1 older male; no data on life experiences provided beyond awareness of the field of study; one might draw from this that the 3 were undergrad students and the older male was a professor/advisor) makes it difficult to draw a solid conclusion about human hearing as a whole.

Sure it takes time and effort and they were able to take a bunch of readings, but they have huge gaping holes that ought to be covered:

How are the readings affected by gender or age?
By foreknowledge of the basis of the experiment? (example: NAM who was older had foreknowledge and understanding, probably a professor, and did much much better on the lag time than any of the other participants: ~2 times better than DDM, 3 times better than HAM and 4 times better than JPR!)
What about Life experiences? Are these people who don't depend on sound localization in their every day life (i.e. are they practiced at determining sound location, or not? Examples of practiced people might be: Hunters, Gamers, Soldiers, Musicians, Sound technicians, or other pursuits that are dependent on being able to accurately determine sound/location)

The range on ability to localize from varying azimuths between participants was (units in degrees)

0 azmiuth: 1.06 (single), 2.13 (lead), and 7.03 (lag)
25 azmiuth: 2.25 (single), 3.24 (lead), and 10.64 (lag)
50 azimuth: 2.34 (single), 4.22 (lead), and 29.45 (lag)

The variance is not terribly large among the 4 participants for single and lead times (although it is enough to make a qualitative difference), but is astoundingly wide when it comes to lag time variation among the 4.

More test subjects who share similar traits (age, sex, life experience) would provide for a better study from which some conclusion might be drawn. The flaw in the study is not a misapplication of the methods, but that 4 uncontrolled data points is simply not enough to extrapolate from.

My hypothesis would tend to be that, when controlled for age/sex and other genetic factors, life experience is likely to be linked to the ability to more accurately perceive sounds.

And I'd hasten to note that, as I pointed out, the study itself verified the primary point I made there is an approximately 1 degree arc of variance when the subjects were looking dead ahead at the target. That's low enough that a subject should have no trouble at all determining the location to within a 5 foot cube.

As for the disdain I've apparently earned by linking to the "popular science article", I would note that the sourcing for that article is pristine peer-reviewed and published works, the latter of which uses Macmillan's study as a reference point. You might be less hasty in the future than to dismiss information without actually checking the sourcing of it.

The papers again, which I highly recommend for anyone who wants to learn about the topic of how people hear and locate the origins of sounds:
Phillips D.P., Quinlan C.K. & Dingle R.N. (2012). Stability of central binaural sound localization mechanisms in mammals, and the Heffner hypothesis, Neuroscience & Biobehavioral Reviews, 36 (2) 889-900. DOI: 10.1016/j.neubiorev.2011.11.003
http://dx.doi.org/10.1016%2Fj.neubiorev.2011.11.003

Letowski T.R. and Letowski S.T. (2012) Auditory Spatial Perception: Auditory Localization, Army Research Laboratories ARL-TR-6016
http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA562292

A study from which harder conclusions could be drawn would be Best, V.; Brungart, D.; Carlile, S.; Jin, C.; Macpherson, E.; Martin, R. L.; McAnally, K. I.; Sabin, A. T.; Simpson, B. A Meta-analysis of Localization Errors Made in the Anechoic Free Field. Proceedings of the International Workshop on the Principles and Applications of Spatial Hearing (IWPASH), Miyagi (Japan): Tohoku University, 2009. which had a sample size of 50,000 localization trials...not 4.

The second source paper indicates that motion is detected after between 300ms (0 degrees) to 1200ms (for 60 degrees).

So, as long as the subject is directly facing (and we know there is no facing in default D&D, although that is an optional rule) the sound, they will be able to detect its motion accurately (within 2-4 degrees) in about a third of a second.

Given that most of combat is simultaneous and continous, and the subject is making no attempt to hide (and therefore making noise as our character in darkness approaches), I would in no way expect them to have any difficulty at all proceeding directly to the enemy because there will be constant opportunity for course correction.

[Segev]

So, using all these examples; the fly on the wall, or the invisible reader, etc; the DM, per RAW, decides if this is a circumstance that is appropriate for hiding. If the DM decides it is indeed one such circumstance then it doesn't matter whether or not the character decides to actively hide or not, the DM has already determined a stealth roll is required. Roll the stealth vs passive perception and move on.Which interestingly enough means that the Invisible condition does literally nothing for the fly on the wall, if said fly would have had potential to go unnoticed just by virtue of being a tiny insect, and raises a question as to what the Stealth check of an inanimate object (e.g. the coin on the floor) is.



BTW, I'm very interested in reading your friend's master's thesis, if a link is available.Doctoral, actually; the jerk skipped Masters altogether. I don't think there is an electronic copy available; my own dissertation is only published physically, though I have a copy or few electronically in my own records.

I don't know that this was in his dissertation, though. I suspect there were a few (or at least one) papers on it; I'll ask him about it. Those likely were published in electronic form.


That's pretty interesting, laser tag as science!

Still, the purpose of that experiment was likely to isolate hearing as the only means of detection. In "real life", there would be other clues that would hint as to the location of an invisible person... a whiff of sweat, rattle of gravel, etc.

Although one might argue that's the point of the perception check.
Actually, once you get out of hearing and sight, humans are pretty terrible at localizing things. (Okay, we can do it VERY well with touch, but that's kind-of begging the question, since we can't detect them with that sense until we are LITERALLY touching them. So.)

I won't claim that there's no way 5e's RAW can't say that the Invisible condition is nearly useless for obscuring your 5 ft. square, compared to anything else that also would let you roll stealth. But I will point out that it's dumb if that is the only way the RAW can be read. (Just as I do wrt the Charmed condition and most spells that are based on it.)

[IShouldntBehere]

Anyway, I just did a totally unscientific experiment with a friend where I closed my eyes in a large room, stuck my fingers in my ears and hummed loudly while they chose a position. I think removed my hands from my ears, had them say one word and I would point to the sound. Turns out they were ~30 feet away to my left, I pointed and was off by about 1 foot from their actual position.

Now that's just one sound, not many sounds as would be occurring in combat, repeatedly, and I was not even facing them as I inevitably would have turned to reconfirm before (in a game) making the attack. So, anecdotally I tried the test you mentioned and it was effectively succesful as 1 foot variance is well within the 5 foot square.

That wasn't the test. What you did was isolate a static target going out it's way to make a specific beacon sound (that is trying to be noisy), along a single plane with an infinitely long "ray" to hit with. To do what you did you only need to figure out if the target is generally to the left or right of you. No one is debating that's fairly easy to do, however that's not locating a target's space.

In D&D terms what you did was choose a corner of your space, such that an infinitely long cone effect originating from that corner would include the target.


The test was to find and track a moving target while tracking effectively tracking it two dimensions that is where to the left & right you it is while also correctly finding the depth to it (how near or far away it is) while it is not intentionally making sounds for you to find, while moving to bring yourself in melee range with safe bopping device.

Seriously it's like I challenged to go fish up a whale shark and you went over to your fish tank, got out the net and scooped up your pet guppy and went "Nailed it"

[MaxWilson]

*snip*So, as long as the subject is directly facing (and we know there is no facing in default D&D, although that is an optional rule) the sound, they will be able to detect its motion accurately (within 2-4 degrees) in about a third of a second.

That's a tendentious reading. You're still very attached to your original "2 degrees" claim, which applies to relative localization, but the Letowski paper reveals a much higher degree of uncertainty as to human precision at absolute localization (which is what matters for invisible creatures in D&D). Quoting:


In general, CE [Constant Error] is the smallest for frontal positions and increases with sound source laterality and elevation. The largest localization errors have been observed for sound source positions behind the listener, especially for sound sources not located on the listener’s interaural plane. For frontal positions and wideband sounds, the reported CEs have been as small as 2°–4° in azimuth and 3.5°–4° in elevation (Bauer and Blackmer, 1965; Best et al., 2009; Carlile et al., 1997; Makous and Middlebrooks, 1990; Oldfield and Parker, 1984a; Razavi, 2009) and as large as 10°–15° in azimuth (Makous and Middlebrooks, 1990; Tiitinen et al. 2004; Tonning, 1970) and 15°–20° in elevation (Bauer and Blackmer, 1965; Tiitinen et al. 2004). For lateral horizontal positions, they are on the order of 10°, and for rear horizontal positions they can be as large as 20°–25° (e.g., Blauert, 1974/2001; Oldfield and Parker, 1984a; Rakerd and Hartmann, 1985). Savel (2009) observed that CE in the horizontal plane (low frequency bands of noise, 50 listeners) has a tendency to increase linearly or logarithmically with the laterality of the sound source.

Rear horizontal positions don't matter because the observer in this scenario is free to turn his head, but the confidently-repeated claim of 2 degree (absolute) localization hasn't been substantiated by anything I've seen mentioned by or linked in to this thread, except by that pop sci article.

[borg286]

Correct me if I'm wrong but if a warlock buddy casts darkness on some foes then ranged attacks have both advantage due to the target being blind to the ranger, and disadvantage due to the attacker not being able to see the target.
If this warlock buddy has Devil's sight and had cast Darkness on himself and simply positions himself on the far side of an opponent then ranged attackers could easily know to attack the square on their side of the center of the darkness sphere.

A side benefit is that any disadvantage that the ranged attack has is canceled like

Being Frightened
An invisible target that the warlock found
Being poisoned
Bring Prone

It is also a great way to cancel out the disadvantage granted by being stunned on a melee/ranged ally.

This seems to also work for a melee ally, but is trickier in conveying where the target is. What are some good ways of taking advantage of this.

A huge benefit/drawback is that it cancels all targeted spells. AOE spells are unaffected, but spells like command never work on you, and they can't be cast by allies on targets in the darkness sphere.

[MaxWilson]

A huge benefit/drawback is that it cancels all targeted spells. AOE spells are unaffected, but spells like command never work on you, and they can't be cast by allies on targets in the darkness sphere.

Not quite all targeted spells. There exist a handful of spells such as Shield of Faith, Cure Wounds, Otiluke's Resilient Sphere, Dispel Magic, Fly, and Slow, which can be cast on specific creatures even if you can't see them.

Probably 80-90% of targeted spells don't work though if you can't see the target.

[Dmdork]

Invisibilty and hiding in combat, is different than Invisibility and hiding outside of combat.

Per RAW:

In combat characters are assumed to be aware of their surroundings and it takes an action to hide.

Out of combat, actions matter less because their is no action economy.

Per the Hiding rules:

The DM decides when circumstances are appropriate for hiding.

Now, as hiding is stated as an action during combat, the basic idea is that whether or not one uses invisibility, they aren't hidden unless they take the hide action and win a contested stealth v perception roll.

Outside of combat, a DM could very well decide that the circumstance for hiding has been met in the case of the invisible wizard reading a book. In that case, the wizard would make a stealth check and it would be opposed by the passive perception of anyone entering the room (or a roll of those entering were actively trying to look for hidden items/creatures).

Me personally, I see it as taking the hide action if a person is invisible and "does nothing (i.e. The invisible wizard leaning against the wall observing)." That is, opting not to take an action and opting not to move, would default to the hide action. But that's just my way to play it.

Thank you all for your input. I think I have enough to go on. Awesome. This post hit home for me. I'm gonna throw up another one about blindness, it may sound like the same thing but I feel it's not...stand by....

[Xetheral]

Invisible
• an invisible creature is impossible to see without the aid of magic or a special sense. For the purpose of hiding, the creature is heavily obscured. The creature’s location can be detected by any noise it makes or any tracks it leaves.

You are misinterpreting "The creature's location can be detected..." as "The creature's location is detected...", but that is not what the rules say. Just because the creature's location can be detected doesn't mean it will be; the rule you quote only states that it is possible (as opposed to detecting an invisible creature's location with vision, which is impossible). Determining whether or not an invisible creature's location is noticed is not specified in the rules, and is therefore up to the DM.



NOTICING OTHER CREATURES
...if neither side is being stealthy, creatures automatically notice each other once they are within sight or hearing range of one another.

Here you are overlooking both the fact that whether or not creatures are within hearing range is left up to the DM, and that fact that nothing says that hearing range is a fixed value. If the DM, taking into account any and all other factors (e.g. the volume of the noise, the background noise, distraction, obstructions) thinks that the invisible creature is definitely within hearing range or outside of it, great! Otherwise, if there is uncertainty as to what hearing range would be under the circumstances, the normal 5e mechanic is to make an ability check....

For hearing the breathing of the unconscious, invisible wizard on the floor, I'd rule that, so long as the room was otherwise quiet, an adjacent creature is definitely within hearing range, and one more than 20 feet away is not. Between those distances, I'd call for a Perception check (with a scaling DC based on distance) to determine if the listener is within hearing range. Making decisions like this is exactly what the RAW tells me, as the DM, to do. (Whether or not that flexibility, and resultant variation between tables, is a good thing or a bad thing is entirely a matter of opinion.)

Ultimately, neither of the rules you quoted support your conclusion that the location of an (non-hiding) invisible creature is automatically known. The closest is the second rule, which supports only the conclusion that there exists a range (determined by the DM based on the circumstances) closer than which determining the location of an invisible creature by sound becomes automatic.

[Vogonjeltz]

That wasn't the test. What you did was isolate a static target going out it's way to make a specific beacon sound (that is trying to be noisy), along a single plane with an infinitely long "ray" to hit with. To do what you did you only need to figure out if the target is generally to the left or right of you. No one is debating that's fairly easy to do, however that's not locating a target's space.

In D&D terms what you did was choose a corner of your space, such that an infinitely long cone effect originating from that corner would include the target.


The test was to find and track a moving target while tracking effectively tracking it two dimensions that is where to the left & right you it is while also correctly finding the depth to it (how near or far away it is) while it is not intentionally making sounds for you to find, while moving to bring yourself in melee range with safe bopping device.

Seriously it's like I challenged to go fish up a whale shark and you went over to your fish tank, got out the net and scooped up your pet guppy and went "Nailed it"

1) Yes, I know I didn't make it the easier test of tracking the movement of a sound, or even repeated noises, and I told the subject to be quiet specifically to make it harder to locate them. I had to implement the very loud humming with my ears plugged device precisely because without it I could hear him walk over (even with my ears plugged).

Essentially it was a total no brainer as to his location if I didn't put in the extra work to avoid hearing his movement. Even with fingers in ears I could hear normal walking from the vibrations on the outside of my ears. This excludes all the other noises a subject in combat wearing armor and running around would be making.

Given that Melee attacks are done from 5 feet away, knowing the direction is basically good enough to locate the space. Ranged attacks being done in a line effectively means the same thing. If you can point at the target, you can plausibly make an attack on the space. And pointing at the target is beyond easy.

2) Maybe I'm focusing too hard on the second to last paragraph, but you've just suggested that sounds themselves have intent. As if sounds were living beings. Could you clarify what exactly you're saying there?

The whale shark/guppy comparison is silly in that I undertook a more difficult task, accurately locating a target who could be anywhere in a 360 degree arc based on a single, relatively quiet, noise. In point of fact, given that the subject ended up being on my back left the degree of error ought to have been something along the lines of 15-20 degrees, but I still managed to point within 1 foot.


Rear horizontal positions don't matter because the observer in this scenario is free to turn his head, but the confidently-repeated claim of 2 degree (absolute) localization hasn't been substantiated by anything I've seen mentioned by or linked in to this thread, except by that pop sci article.

You literally bolded the 2 degree note in your quote!: "For frontal positions and wideband sounds, the reported CEs have been as small as 2°–4° in azimuth"

Here is a sample of notes from the Letowski paper regarding the 2 degree arc (I'm including the document page number and the pdf number that corresponds to for easy reference):

1) "For example, Pollack and Rose (1967) observed that with no head movements, changing the signal duration from 3 ms to 1 s reduced
the average localization error from 10° to 2°." (page 18 of the document, type in page 28 of the pdf)

Same page: "In one notable study, Noble and Gates (1985) allowed the listeners to move their head and body (while remaining seated) and control the duration of the presented stimuli. They reported far better localization accuracy than was earlier reported by Roffler and Butler (1968b), who used similar signals but restricted the listener’s movements."

2) "For wideband stimuli and low frequency tones, the MAA is on the order of 1° to 2° for the frontal position (Mills, 1958; 1972; Perrott and Saberi, 1990)," (page 56 of the document, type in 66 for the pdf)

3) "At low horizontal angular velocities (below 20°/s), the MAMA at the midline (0°) is relatively small (on the order of 2–8°; Perrott and Marlborough [1989] reported 1°) but becomes larger (10°–20°) as velocity increases (Carlile and Best, 2002; Chandler and Grantham, 1992; Harris and Sergeant, 1971; Perrott, 1982; Perrott et al., 1993; Saberi and Perrott, 1990). Grantham (1997) reported MAMAs of 4.8° and 7.8° at velocities of 20°/s and 60°/s, respectively. A MAMA of 20° was also reported for a velocity of 180°/s by Chandler and Grantham (1992) and for a velocity of 360°/s by Grantham (1986) and Perrott and Musicant (1977). Strybel et al. (1992b) reported that at a velocity of 20°/s, the initial position of the sound source did not significantly affect the MAMA for azimuth locations in the ±40° range. Within this range, and at elevations below 80°, the MAMAs were surprisingly small (1–2°) but increased to 3–10° outside of this range. However, Chandler and Grantham (1992) reported MAMAs being 1.5 to 3.0 times larger at a 60° azimuth than at the midline (0°). Some variability in the reported data may be caused by the degree of spatial adaptation to the initial position of the subsequently moving sound source available to the listener (Getzman and Lewald, 2011)." (page 80, pdf page 90)


#1 suggests that ongoing noises are much easier to locate (5 times easier in the example given, and it only lasted 1 second)

#2 suggests that there's a smaller degree of error than we are likely to encounter on a grid of 5 foot squares.

I'd also note that you were referencing Absolute Localization on your quote, which is the kind of localization that my totally non-scientific would have measured. Which is to say: "Absolute localization is the identification of the direction of an incoming sound in absolute terms, i.e., without using a previously heard sound as a reference point."

It's worth recognizing they aren't the same thing, but that the higher degree of error you noted is only when there's no reference point. When there is a reference point (i.e. continuing sounds, repeat sounds, etc...) accuracy goes up dramatically. Ditto when the subject is allowed to actually move their heads to aid in localization (which would be the obvious case in D&D).

#3 indicates that determining movement requires more movement as the sound source moves futher lateral to the subject.

The important take-away from this is that if a listener turns to face a moving noise, the listener actually reduce the minimum distance the sound source has to move to recognize the difference.

As the use of laser pointers was mentioned earlier, I found the reference to this study that post-dates the 93 one quite interesting:
"The most precise technique seems to be the laser pointing technique. Seeber (1997), for example, reported errors on the order of only 0.2° for laser pointing, which seem to be an order of magnitude smaller than the errors reported for other methods. It seems that the laser beam provides important visual feedback to the listener leading to more accurate sound source localization (Razavi, 2009, p. 216)." (pg 140, pdf 150)