Surprise grappling the invisible

[Millstone85]

Recently, I sent my familiar ahead to check on a fire in town and it found another PC in the middle of a heated conversation *ba dum tss* with the city watch. The player was told that she sensed a tiny presence on the ground but saw nothing there. She decided to catch the thing.

The DM ruled that she needed to make an ability check, I forgot which one, against my familiar's passive Dexterity (Stealth) score. She missed and presumably closed her hands on empty air. I then had my familiar reappear from under a basket, so she knew that was just it.

I have since reread the rules on surprise, grappling and invisibility, because I am curious about how far the DM's solution was from the book. But I can't quite piece it together. Can you help me with that?

[Yuki Akuma]

You'd need to make an opposed Wisdom (Perception) check to locate the invisible creature, then an opposed Strength (Athletics) check to actually grab it.

The Strength (Athletics) check would probably be at disadvantage, using the rules for attacking an invisible creature when you know its square, but I don't remember if it's explicit about that.

Since this character flubbed her Wisdom (Perception) check, though, she doesn't know what square the familiar is in, so she doesn't get to roll Strength (Athletics) to grab it. So missing after just one check is fine.

The familiar probably should've rolled its own Dexterity (Stealth) check to oppose the Wisdom (Perception) check, but using the 'passive score' is fine really.

I don't see why either combatant would be surprised in this case.

[Millstone85]

I don't see why either combatant would be surprised in this case.My familiar wasn't expecting this combat. First, it didn't think it would be detected amidst all the noise and agitation. The DM even apologized to me for revealing the character's supernatural insight in this fashion. Secondly, the character had seen my familiar turn invisible before so a "Psst, is that you?" seemed more likely. Anyway, the DM used a passive score to account for the surprise.


You'd need to make an opposed Wisdom (Perception) check to locate the invisible creature, then an opposed Strength (Athletics) check to actually grab it.
Since this character flubbed her Wisdom (Perception) check, though, she doesn't know what square the familiar is in, so she doesn't get to roll Strength (Athletics) to grab it. So missing after just one check is fine.

The familiar probably should've rolled its own Dexterity (Stealth) check to oppose the Wisdom (Perception) check, but using the 'passive score' is fine really.That may have been exactly what we did and I just didn't understand on the moment.


The Strength (Athletics) check would probably be at disadvantage, using the rules for attacking an invisible creature when you know its square, but I don't remember if it's explicit about that.Well, the grapple attempt replaces an attack. It would also make sense in general.

[metaridley18]

If the familiar was Hidden, having taken an action to make a Dexterity(Stealth) check, the DM should have compared that result against the PC's Passive Perception. If the Passive Perception were greater than the Stealth check, the PC would have sensed the familiar, and known its location. If not, the PC would not have known its location and shouldn't have "sensed a tiny presence."

If, having beaten the familiar's Stealth DC with Passive Perception, the PC attempted to grapple it, there would have been no change to the Strength(Athletics) check to grapple.

Invisibility does not grant anything except the ability to not be seen, a.k.a., the ability to Hide with nothing obscuring you, and adv/disadv to your attacks/attacks against you. Once you are Hidden, everything is resolved using the Hide/Stealth rules, with the exception that you can maintain Hidden status irrespective of visual conditions, since you are Invisible.

If you are Invisible, but didn't attempt to Hide, or if a creature overcame your Stealth check with their passive perception, the only thing that Invisibility grants you is the Advantage on attack rolls and disadvantage on attack rolls against you. Not saves, or ability checks.

Chalk it up to an imperfect Invisibility spell, or making noise walking around, or dust in the air, or whatever you will, if you didn't take a special action to Hide or someone defeated your Stealth check regardless, they know exactly where you are by the way the Invisibility condition is worded. It's a subtle nerf to the Invisibility spell from earlier editions that tends to surprise people.

Now, of course a reasonable DM is going to rule that you don't know exactly where every creature is all the time, even if you can't see them. But in general, so long as one of your senses can perceive a creature, they aren't Hidden from you unless they make a Dex(Stealth) check and succeed.

[Millstone85]

If you are Invisible, but didn't attempt to HideI need not spell out to the DM that my invisible familiar is in fact trying to be stealthy. In combat, yes, where the Invisibility and Hide actions would take two different turns of the familiar. But we weren't in combat, at least not until a grapple was attempted. And if the DM doesn't ask for a Dexterity (Stealth) check, I sure won't.


there would have been no change to the Strength(Athletics) check to grapple.Since a grapple is defined as a melee attack, that's one case where the "disadvantage on the attack roll" precision is actually important. I hope there aren't many others.


If not, the PC would not have known its location and shouldn't have "sensed a tiny presence."It is apparently a gift of some sort, connected to a yet unrevealed part of the character's backstory. I don't know how it works beyond the "You sense a tiny presence." thing. If the game mechanics are already completely broken because of it, well then they are.

[Zorku]

There's a quirk with the hidden condition* here. You only retain your hidden status relative to another creature if you have some means of hindering the senses they use to locate you**. The handbook usually refers to this as being obscured, but because we're dealing with a sense other than sight in this case, being visually obscured is meaningless right now.
*Hidden isn't a "condition," but rather a state between the creature attempting to be sneaky, and any other particular creature, as in, you can be hidden from a guard but not his dog. In most hostile encounters one creature that notices somebody skulking around will inform their allies immediately, but if they don't tell others for some reason then nobody else will know, and you will be hidden to a bunch of hostile creatures but not that particular one that sensed you.
**At DM discretion you can give an NPC tunnel vision so that they don't notice sneaky things happening in what would normally be their line of sight.

The language in the hand book doesn't do a great job of explaining this, but there's some errata kicking around that spells this out in this way. Full cover is required when you take the hide action (as in, the folks you wanna hide from are not present to track your movements,) and then at least some cover is required to not show up on their personal radar with a loud "ping!" noise. The errata explanation still kind of sucks, so make sure your DM understands this the same way that you do before you rely on it, but as far as I can tell this is RAI and the simplest interpretation of RAW.

I don't know exactly what sense that other character has, but if it allows them to pinpoint creatures they cannot see then your familiar might as well have been trying to hide right in front of a normal human, in broad daylight, by standing veeeery still.

[Millstone85]

I don't know exactly what sense that other character has, but if it allows them to pinpoint creatures they cannot see then your familiar might as well have been trying to hide right in front of a normal human, in broad daylight, by standing veeeery still.Eh, it works for Granny Weatherwax. Stillness and the certitude that you belong here.

Seriously now, I don't know either. But the idea, it seems, is that my familiar was too taken aback to even try to dodge, yet the other character's hands closed on thin air. So "pinpoint" must be too strong a word. She knew about a presence, of tiny size, near her.

You can hide from creatures actively searching for you, and even in the middle of battle, so your existence and proximity being known can't be in contradiction with being hidden.

[Zorku]

Eh, it works for Granny Weatherwax. Stillness and the certitude that you belong here.

Seriously now, I don't know either. But the idea, it seems, is that my familiar was too taken aback to even try to dodge, yet the other character's hands closed on thin air. So "pinpoint" must be too strong a word. She knew about a presence, of tiny size, near her.

You can hide from creatures actively searching for you, and even in the middle of battle, so your existence and proximity being known can't be in contradiction with being hidden.

I'm wary about using the term "surprise," as it specifically refers to the type of combat where you attack a creature that did not yet know about your presence.

Otherwise, I would basically agree with your speculation of how things should have worked, but chastise you for assuming that everything has been done by the book, and that the DM interpreted everything pretty much the same way we have. There's not enough information here to warrant the conclusion that the character has some homebrewed form of spider-sense. It's certainly possible that the DM has given that to them, but before I know more I'm going to stick with mechanics that are expressly within the book.

[Millstone85]

There's not enough information here to warrant the conclusion that the character has some homebrewed form of spider-sense.
The DM even apologized to me for revealing the character's supernatural insight in this fashion.
It is apparently a gift of some sort, connected to a yet unrevealed part of the character's backstory.What more do you want? :smallconfused:


I'm wary about using the term "surprise," as it specifically refers to the type of combat where you attack a creature that did not yet know about your presence.Personally, I would extend the mechanic to attackers not previously identified as enemies. Many surprised convives at the Red Wedding. But there is also the fact that surprise has nothing to do with ability checks. So yeah, you are right.


Otherwise, I would basically agree with your speculation of how things should have worked, but chastise you for assuming that everything has been done by the book, and that the DM interpreted everything pretty much the same way we have.I only recognized the possibility.

[Plaguescarred]

If the familiar was only invisible and not hidden, there should have been no surprise as it would have been noticed. Grappling rules would apply as normal since being invisible doesn't impede on ability checks.

If the familiar was invisible and hidden, then a Stealth check should have been compared with the Passive Perception score of the guard to see if it's noticed or not and to determine surprise. If the guard noticed it, it could have tried to grapple it as normal. If it didn't noticed it, then the guard would have had to correctly guess the right space the hidden familiar was occupying in order to try to grapple it.

[Zorku]

What more do you want? :smallconfused:

I only recognized the possibility.

There's a big difference between "15ft blindsight" and comic booky "spider senses."
The first example is something that exists within the confines of how the game works, the second is just dm fiat, which sort of exists, but is a strange sort of thing to apply to a character. Because we know next to nothing about this power, even lacking a name for it, there is no way to set boundaries to what's going on here. Maybe the character knows how many sets of eyes are looking at them at any time, maybe they can smell CO2 as precisely as an insect, maybe they read the surface thoughts of all creatures in their vicinity. There's no way to tell those apart from this scene and the term "supernatural ability," so we're left guessing at what kinds of things a person we don't know might think up.

Or in short form, proposing that particular speculation was unwarranted.


Personally, I would extend the mechanic to attackers not previously identified as enemies. Many surprised convives at the Red Wedding. But there is also the fact that surprise has nothing to do with ability checks. So yeah, you are right.I like having that kind of option, but this edition leaves that up to DM fiat. The language in the book only ever gets so close as "a (creature) that doesn't notice a threat is surprised at the start of the encounter," and only talks about this in terms of stealthily sneaking up on others. A lot of people are going to read the paragraph and thing the rules don't give you any way to recreate the red wedding *cough*theresoneoftheminthisthreadrightnow*cough* while others will scratch their heads and say "well they notice somebody using disguise self to look like their own mother, but they didn't notice that it's actually someone they should view as a threat..."

I'd say that the vagueness here is probably intentional, as they don't want to mandate that every by-the-book game have more ways of getting a surprise round in combat, but also want to make it easy for a DM to allow these kinds of plans if they think it's a good idea and it fits the tone of their game. This all the difference if you think that an assassin is someone that launches deadly ambushes, or if they're somebody that has the power to slip around in the shadows before they start killing all of the named NPCs in the royal court.


If the familiar was only invisible and not hidden, there should have been no surprise as it would have been noticed. Grappling rules would apply as normal since being invisible doesn't impede on ability checks.

If the familiar was invisible and hidden, then a Stealth check should have been compared with the Passive Perception score of the guard to see if it's noticed or not and to determine surprise. If the guard noticed it, it could have tried to grapple it as normal. If it didn't noticed it, then the guard would have had to correctly guess the right space the hidden familiar was occupying in order to try to grapple it.
OP already basically said "well obviously it was hidden!" in a very "of course I'm checking for traps when I walk down a dungeon corridor!" kind of way. I would think that this edition generally affords him that, given what he was trying to do, but I kind of doubt that the DM here has done a deep dive into the exact mechanics of how stealth is supposed to work.

[Plaguescarred]

OP already basically said "well obviously it was hidden!" in a very "of course I'm checking for traps when I walk down a dungeon corridor!" kind of way. I would think that this edition generally affords him that, given what he was trying to do, but I kind of doubt that the DM here has done a deep dive into the exact mechanics of how stealth is supposed to work.OP said he's I am curious about how far the DM's solution was from the book. 5E rules for Stealth don't rely on passive check for Stealth, but active one. If the familiar was hidden, he would have made an active Stealth check and know it's Stealth score.

No Stealth check means no score to compare to any guard's Passive Perception.

If the DM ruled it out as hidden and not detected anyway, then the guard would have had to guess the correct space to grapple the familiar.

This is where it's away from the book basically.

[Millstone85]

If the guard noticed it, it could have tried to grapple it as normal.No guard tried to catch my familiar. The other PC is a wizard and she was talking to guards.

Come to think of it, the guards made no comment about an invisible creature or the wizard's sudden wrestle with the ground.


Or in short form, proposing that particular speculation was unwarranted.I don't get what speculation you are talking about exactly.

There being a supernatural ability at play isn't speculation on my part. Again, the DM told me. And yes, it is frustrating to not have the details of it.

Is it about the speculation that my familiar might still have counted as hidden to the other PC, what with the supernatural ability not necessarily being a direct sense like blindsight? Well, I decided to send a mail to the DM about that. Was my familiar still considered "hidden" from the PC? A simple enough question, I hope.


OP already basically said "well obviously it was hidden!" in a very "of course I'm checking for traps when I walk down a dungeon corridor!" kind of way. I would think that this edition generally affords him that, given what he was trying to doI can think of a few reasons why a PC might not actively check for traps while walking down a corridor. Maybe the player wants to roleplay someone who is green at adventuring. Maybe the place has not yet been identified as dungeony. Maybe the DM has decided of a time cost and the party is in a hurry right now. But when a character sends an invisible familiar ahead, would you really pull the "You didn't say stealth" card and feel good about yourself?

Also, it is more "well obviously it was trying to hide" than "well obviously it was hidden".


but I kind of doubt that the DM here has done a deep dive into the exact mechanics of how stealth is supposed to work.Possible. He could also have forgotten and not felt like rereading the book for such an incidental part of the story.


5E rules for Stealth don't rely on passive check for Stealth, but active one.Yeah, whether the DM was talking about the game's definition of surprise or not, it didn't really make sense to use a passive score.

[Zorku]

I don't get what speculation you are talking about exactly.Spider. Sense.


There being a supernatural ability at play isn't speculation on my part. Again, the DM told me. And yes, it is frustrating to not have the details of it.

Is it about the speculation that my familiar might still have counted as hidden to the other PC, what with the supernatural ability not necessarily being a direct sense like blindsight? Well, I decided to send a mail to the DM about that. Was my familiar still considered "hidden" from the PC? A simple enough question, I hope.That would be simple enough if I were the DM. Based off of my idea of what an average DM is like, they probably don't actually understand how the book explains what "hidden" even is, and while a flat yes/no answer should tell you a lot about that wizard's supernatural ability, I don't expect it to in this case.


I can think of a few reasons why a PC might not actively check for traps while walking down a corridor. Maybe the player wants to roleplay someone who is green at adventuring. Maybe the place has not yet been identified as dungeony. Maybe the DM has decided of a time cost and the party is in a hurry right now. But when a character sends an invisible familiar ahead, would you really pull the "You didn't say stealth" card and feel good about yourself?Depends on the edition. In 5th I wouldn't feel good about that but in 2nd... sure why not? I don't know if this DM views 5th the way I do, or if they think it's closer to how I view 2nd. There are a lot of people that do it the one way, the other, and even more in between.

Based off of your experience, it could still go either way. You don't seem to be on the 2nd edition side of the spectrum, but your DM does things that don't make much sense to you, so.... idunnoman.


Possible. He could also have forgotten and not felt like rereading the book for such an incidental part of the story.On first pass you tend to pick up that heavy obscurement is good for hiding, and that generally you shouldn't be in plain sight while hiding, but the original print of the PHB didn't really direct your attention to the idea of moving around while hidden, so the natural interpretation is something akin to "you've got to keep the obstacle you'd hiding behind between yourself and the target," and even with all the tweets and errata and such that have come out since then I can't always convince other DMs that that's neither the original intent nor the current official rules as written.

In order to think that 5e's stealth lets you go pretty much wherever you want for as long as you want so long as you don't ever step completely out of cover (relative to whatever target(s) you want to be hidden from,) and don't do anything so reckless that the DM rules you need another check to stay hidden you probably got that idea poking around on message boards, or just kind of assumed that was the case before you even read the rules to begin with.


Yeah, whether the DM was talking about the game's definition of surprise or not, it didn't really make sense to use a passive score.
That quote from plagued reads really strangely to me when it's clipped out all on its own like that. Surprise rounds, as in initiating combat with an attack made from stealth, explicitly compare stealth checks against passive perception, and outside of the context of combat you're only fighting against active checks if some creature becomes suspicious that there's something for them to find.

There's an 'exception proves the rule' line on p60 of the basic rules.
"In combat, most creatures stay alert for signs of danger all around, so ... it usually sees you." The "usually" here is explained in the next sentence as a DM fiat thing. Since this specifies "in combat," we can see that it doesn't apply more broadly, and the next paragraph explains how passive perception is generally how you decide if a creature sees someone hiding without actively searching for them.

All of this basically means that you don't go doing active checks for stealthy creatures unless they've made noise or left tracks (or in the case of other senses, if they've given you suitable evidence of their presence.)



I'm too short on time to trace back to what plague was originally saying, so hopefully surrounding context makes this less blatantly incorrect.