Passive Perception

[deljzc]

Do you change passive perception depending on what monsters are "supposed to be doing"?

If monsters are on "lookout" duty or guards is that a different passive perception that what is in the stat block?

Or do you make stealth checks at disadvantage in those cases?

Do any other environmental factors adjust the passive perception or do you just concentrate on the stealth roll? Limited hiding areas? One way in/one way out?

I am just trying to learn and understand those first moments of encounters and how stealth, passive perception and surprise all work exactly.

Do most of your adventure parties just tell you ahead of time they are ALWAYS in "stealth mode" to at least give them a chance at surprising monsters?

Thanks in advance.

[Man_Over_Game]

Do you change passive perception depending on what monsters are "supposed to be doing"?

If monsters are on "lookout" duty or guards is that a different passive perception that what is in the stat block?

Or do you make stealth checks at disadvantage in those cases?

Do any other environmental factors adjust the passive perception or do you just concentrate on the stealth roll? Limited hiding areas? One way in/one way out?

I am just trying to learn and understand those first moments of encounters and how stealth, passive perception and surprise all work exactly.

Do most of your adventure parties just tell you ahead of time they are ALWAYS in "stealth mode" to at least give them a chance at surprising monsters?

Thanks in advance.

Good questions! Stealth has always been kinda awkward to work properly in 5e. The best advice most DMs have settled on is "use your gut".

For more technical advice, I'd recommend just rolling against the creature's passive perception, unless the creature is actively looking under intense or stressful conditions. A good rule of thumb is to only roll dice for each side that is impacted by stress or chaos.

Players who are under stressful conditions (chaotic) against an inanimate object (no chaos) make their roll against a static DC.
Players who are under relaxed conditions (no chaos) against an inanimate object (no chaos) generally pass/fail without the need for a roll.
Players who are in a heated debate (chaotic) against a political opponent (chaotic) would both roll against one another.



There's little chaos involved for a guard who's out on his regular patrol, especially when compared to a guard that's chasing down a fleeing Player. Creatures that are too distracted to actually pay attention should suffer Disadvantage on their Perception (or a -5 to their passive).

The thing is, you kinda want your players to resort to stealth to solve their problems to make things exciting and dramatic. The weaker you make stealth, the more you're having your players not use it. If it can't solve their problems, they won't use it.

Some parties try that kind of stuff where they say they're "always in stealth mode", and that's fine with the right checks-and-balances. Passive skills should only be checked when it's assumed they're constantly being rolled. Guards are constantly rolling Perception, so you resort to their Passive Perception (effectively an average of multiple rolls). However, rolling for a skill generally requires them to regularly uses their action.

That is, a party that is constantly in "stealth mode" is assumed to not be using their Actions for anything else. They aren't tracking where they are on a map, they aren't paying attention to their surroundings, they aren't casting Detect Magic, etc. They're focused on being stealthy, so that's all that they do. And your job as a DM is to give them what they ask for, just as long as they understand what doing so means. You also walk slower if you're sneaky while travelling, so it's unrealistic to sneak everywhere if you have a time-sensitive issue.

The best way to use Surprise is to gauge whether the creatures/players were aware of an immediate threat or not. Looking for a threat is not the same as being aware of a threat. For this reason, you can't have enemies sneak into the middle of a fight and 'Surprise' the players after the first round of combat, since the Players were already aware of a threat (however, normal Hiding rules might apply for the new enemies).

[deljzc]

So if you don't have enemies sneak into a fight hidden then does that apply to PC rogues as well?

Once combat starts, you don't allow hiding anymore? Or maybe you allow hiding but no surprise?

Does hiding during combat only become for defensive purposes then? Just to get out of combat? Not with the idea of getting out of combat only to come back in later rounds with surprise attack?

[Man_Over_Game]

So if you don't have enemies sneak into a fight hidden then does that apply to PC rogues as well?

Once combat starts, you don't allow hiding anymore? Or maybe you allow hiding but no surprise?

Does hiding during combat only become for defensive purposes then? Just to get out of combat? Not with the idea of getting out of combat only to come back in later rounds with surprise attack?

Small clarification:

Surprise does NOT equal Hidden.

Being Hidden can lead into Surprising the enemy, but only if the enemy wasn't aware there was a threat in the first place.


Simply put:

A creature that isn't hidden is immediately spotted as soon as another creature could realistically do so.
A creature that's Hidden is Unseen until they do something that gets them spotted (like attacking), or are revealed to an enemy (usually through a Perception check or just walking into obvious Line of Sight).
A Hidden creature that gets the jump on an enemy creature that wasn't aware of a threat causes the enemy creature to be Surprised for the Round.


For example, you can Hide behind a tree or a building in the middle of combat. From there, you can take a potshot with Advantage (as you were Hidden/Unseen during your attack). Lightfoot Halflings can even hide behind their allies. This is different than walking behind the tree or building, since you're not taking any extra precautions in hiding what you're doing.

So you can Hide as many times as you want in combat, generally to conceal whatever it is you're doing next. However, Surprise is something that should only ever come up on the first round. The only exception I could think of to that last bit is if there were creatures that weren't aware of combat/threats during the first rounds, in which case it's THEIR first round of combat.



An important distinction from the developers is that a creature that could remain hidden should. If, for example, your Rogue hides on the dark side of a building and some enemies run past, they'd normally have a direct line of sight to the Rogue and spot him. However, since the Rogue could still be hidden, and none of the enemies are actively searching for him (as they're running past, not regularly spending their Actions for Perception checks), he should still be considered Hidden until the Rogue inevitably does something completely stupid to reveal himself.

[Lunali]

So you can Hide as many times as you want in combat, generally to conceal whatever it is you're doing next. However, Surprise is something that should only ever come up on the first round. The only exception I could think of to that last bit is if there were creatures that weren't aware of combat/threats during the first rounds, in which case it's THEIR first round of combat.

A lot of the confusion on this is the result of their choice of wording. I think there would be a lot less confusion if it were called flatfooted instead of surprised.

[djreynolds]

It's weird because passive perception is strong numerically. It's +10 and whatever.

So on guard duty... You are passively perceiving.

Suddenly something catches your attention. Now you must decide to act... You must initiate action.

Either you focus your senses on perception or focus on clues and investigate.

At this point you're almost rolling initiative because you're acting as if something caught your attention.

Until they act... the guards are passively perceiving... until something makes them act. Like a failed stealth check.

The tough thing to judge is who acts first.... the guard or you?

[deljzc]

So surprise is only at the beginning of combat and only when certain conditions allow (the party is trying to be quiet/stealthy and the terrain allows).

Hiding is a state at any moment (before, during or after combat).

And if the DM chooses, attacks from a hidden state MIGHT be with advantage against a distracted opponent.

[BurgerBeast]

So surprise is only at the beginning of combat and only when certain conditions allow (the party is trying to be quiet/stealthy and the terrain allows).

Hiding is a state at any moment (before, during or after combat).

And if the DM chooses, attacks from a hidden state MIGHT be with advantage against a distracted opponent.

All good except the last bit (no MIGHT). An attack always has advantage IF the target cannot see the attacker. Since hidden implies unseen, a hidden attacker ALWAYS has advantage (as usual, advantage may be cancelled by disadvantage).

[Man_Over_Game]

So surprise is only at the beginning of combat and only when certain conditions allow (the party is trying to be quiet/stealthy and the terrain allows).

Hiding is a state at any moment (before, during or after combat).

And if the DM chooses, attacks from a hidden state MIGHT be with advantage against a distracted opponent.


All good except the last bit (no MIGHT). An attack always has advantage IF the target cannot see the attacker. Since hidden implies unseen, a hidden attacker ALWAYS has advantage (as usual, advantage may be cancelled by disadvantage).

To expand on this:

An Unseen creature effectively:

Cannot be targeted by spells (but might be hit by an AoE)
Has Advantage to attack a creature that cannot see him.
Has Disadvantage to be hit by a creature that cannot see him.


An Invisible creature that isn't hiding (like being in the middle of a room, swinging a sword) is Unseen. A Hidden creature is Unseen until he's revealed.

To be Hidden, a creature must take the Hide action against all non-allied creatures that currently know where you are. If a Rogue runs behind a building and takes the Hide action, he rolls against the highest enemy Passive Perception who knew where he was. THAT'S who he's trying to hide from, and he's Hidden if he succeeds.
A Hidden creature:

Needs to be Unseen to initiate being Hidden
Is Hidden until:
A creature spots him by gaining obvious vision or by making a successful contested Perception check against the Hidden Creature.
The Hidden creature does an action that would reveal them (like attacking or casting a spell).
Is considered Unseen/Unheard while they're appropriately Hidden (that is, a creature is effectively invisible/silent indefinitely until something causes them not to be)


If a creature was Hidden, and nobody is on the lookout for any suspicious activity, that creature remains Hidden.

A creature is Surprised if they were unaware of a threat while the threat initiated combat on them. For example, teleporting into a room may result in its occupants being Surprised, even if the invaders weren't Hidden. Hidden simply becomes a means of closing distance to create Surprise, but it's not mandatory.

That's about it.

If you're confused about whether or not you want to use Passive skills vs. rolling, try to remember that Passive skills are used in an attempt to make things seamless and consistent and to reduce the number of rolls at the table. Rolling once per round to see if the guard patrol doesn't spot the Hidden party this round is fine. Rolling once per guard each round to do the same is not.

Just keep in mind that the more rolls you have that decide failure, the more difficult it will be for the players. If the players, for example, have to spend 6 rounds sneaking their way out of the castle, and you roll to see if the guards spot them each round with a 20% chance of spotting them (17 out of 20), that leaves the players with a 38% total chance of failure. That number seems fine, but most DMs would have their guards spot the party on something less than a 17, because their instinct tells them that 17 is too high. The correct mentality is that rolling a 17 once is too high.

[Lupine]

Just keep in mind that the more rolls you have that decide failure, the more difficult it will be for the players. If the players, for example, have to spend 6 rounds sneaking their way out of the castle, and you roll to see if the guards spot them each round with a 20% chance of spotting them (17 out of 20), that leaves the players with a 38% total chance of failure. That number seems fine, but most DMs would have their guards spot the party on something less than a 17, because their instinct tells them that 17 is too high. The correct mentality is that rolling a 17 once is too high.

Could you explain this to me, I’m not sure I understand that.

[prabe]

Could you explain this to me, I’m not sure I understand that.

Another way of thinking about this is that multiple rolls, where any single successful roll indicates success, is effectively like rolling with advantage--but better--and multiple rolls, where any single unsuccessful roll indicates failure, is effectively like rolling with disadvantage--but worse.

Examples (not saying they're good play or good DMing, and ignoring the idea of group checks):

If you have a party of 5 PCs roll Wisdom (Perception) to spot [thing], where the DC is 20, the party has five chances to spot it, whereas advantage would give 2.

If you have that party of 5 PCs roll Dexterity (Stealth) to sneak past [thing], where the DC is 20, the party has five chances to fail, whereas disadvantage would give 2.

[Greywander]

Could you explain this to me, I’m not sure I understand that.
Here's an example. Let's say you flip one coin. On a heads, you succeed, on a tails, you fail. 50% chance of success.

Now let's say you have to flip the coin three times. You need to get heads every time to succeed. If you get tails even once, you fail. Each flip has a 50% chance of success, so the total odds are 12.5% chance of success.

Ergo, if you have the party roll three stealth checks, and failing even one of them causes them to be detected, then it becomes much more difficult than if they only need to roll one check.

What you could do instead is require three successful rolls to pass, or three failed rolls to be spotted, which should even out the odds. Failing one roll might cause a noise that brings a guard over to investigate, but succeeding on subsequent rolls would mean you still evade detection. All that said, while multiple rolls can help create tension and drama, it also drags things out, so sometimes a single roll is better since it goes quicker.

[Man_Over_Game]

Another way of thinking about this is that multiple rolls, where any single successful roll indicates success, is effectively like rolling with advantage--but better--and multiple rolls, where any single unsuccessful roll indicates failure, is effectively like rolling with disadvantage--but worse.

Another way of thinking about it is body armor. This body armor protects 90% of attacks being shot at you. Sounds good, right?

What if I shot you 10 times? Would you still feel safe? No, because it takes a single failure for the catastrophic to happen. Failure only has to happen once.


If a Rogue goes in solo and succeeds on his initial Hide action, and then is told to make multiple more rolls over the course of the scenario, each of those is their own chance for catastrophic failure. Because DMs often use rolls to allow players to do things, more rolls means more denial.

It boils down to this: The more the DM rolls to see if you succeed, the less you will succeed.

When done well, rolling generates a good balance of reward vs. conflict. Sometimes, it can be oppressive, and the problem is that an inexperienced DM will just blame it on the dice ("Sorry, pal. Dice says you lost, so you lose"). A DM could be making this mistake and never know it.




An easily visible example of this is a Barbarian on a second floor staircase, wanting to swing from the chandelier and jump on the enemy.


DM tells him to roll his Athletics for the jump. Barbarian makes it. (20% chance of failure)
DM tells him to roll an Acrobatics for the swing. Barbarian makes it. (30% chance of failure)
DM tells him to roll another Athletics for the jump. Barbarian fails. (20% chance of failure)
DM says the Barbarian doesn't make his attack and falls prone.



Note how the attempt fails as soon as the Barbarian gets a single failure. Whether it was at the start or near the end, those dice were all called by the DM, and all would have caused the attempt to fail on a bad roll. Individually, they're fine, but multiple rolls to grant your players a single reward is a problem.

Where a DM may think that more rolls make the game more realistic and immersive, a Player will simply see an exciting opportunity...and decide to be boring and take the Attack Action. Anything else is just too much of a risk to be worth it. If you don't want your players to take boring actions, don't roll too often to determine if they fail.

Instead, if you want to use multiple rolls, use them to determine a degree of success, rather than a degree of failure. For example, you could have the Barbarian roll a single Athletics check to make the attempt (failure as normal), and he gets an additional +1 to his attack and hit for every successful Athletics roll he makes after that until he stops rolling a success. This is a great means of rewarding your players who invested heavily into skill-based builds, as math favors this far greater than just increasing the DC from 15 to 20. That is, request x3 DC 15 rolls, instead of a single DC 20 roll.

The only other time I'd recommend multiple rolls to determine failure is if the scenario is one where they are taking an excessively great risk. Infiltrating the King's vault SHOULD have a 20% chance to fail each round, since the guards aren't looking for a particular threat, but they're also fairly well trained. Without additional resources, the party should turn back and reevaluate their approach, unless they want to bet on getting lucky and pull off the heist in as few rounds as possible.

[Segev]

Where a DM may think that more rolls make the game more realistic and immersive, a Player will simply see an exciting opportunity...and decide to be boring and take the Attack Action. Anything else is just too much of a risk to be worth it. If you don't want your players to take boring actions, don't roll too often to determine if they fail.

If you want to use multiple rolls, use them to determine a degree of success, rather than a degree of failure. For example, you could have the Barbarian roll a single Athletics check to make the attempt (failure as normal), and he gets an additional +1 to his attack and hit for every successful Athletics roll he makes after that until he stops rolling a success. This is a great means of rewarding your players who invested heavily into skill-based builds, as math favors this far greater than just increasing the DC from 15 to 20. That is, request x3 DC 15 rolls, instead of a single DC 20 roll.

The only other time I'd recommend multiple rolls to determine failure is if the scenario is one where they are taking an excessively great risk. Infiltrating the King's vault SHOULD have a 20% chance to fail each round, since the guards aren't looking for a particular threat, but they're also fairly well trained. Without additional resources, the party should turn back and reevaluate their approach, unless they want to bet on getting lucky and pull off the heist in as few rounds as possible.

5e also discourages rolls for success unless the outcome is seriously in doubt. In this case, does it really make it more interesting for the Barbarian to try this and fail? No, because, as you said, he can always just choose to attack. Now, you don't want the scrawny wizard who can barely walk down a corridor without tripping over his robes automatically succeeding at this, either; you'd actually prefer he just take a boring old attack, because him suddenly flipping around like Erol Flyn and Black Widdow's love-child is immersion-breaking. So, how do you distinguish it? Well, ask yourself if the Barbarian can make the jump distance (no roll here; check his Strength and the number of feet he's trying to jump, first to the chandellier, then to the enemy), then ask him if he's proficient in Acrobatics.

If he can make the jump distance and is proficient in Acrobatics, just assume he's got the prowess to make this dramatic maneuver work. It will be more fun for him, it validates his build choices, and it doesn't actually cause any problems, balance-wise.

[Lunali]

The discussion here is why I both love and hate the rogue ability reliable talent. On one hand, it makes it actually possible to sneak through places when the DM asks for rolls whenever you do something that would be risky.

On the other hand it takes the tension out of a lot of checks that would normally have a small failure chance and makes for a radically different DC gradient, increase the DC by 1 and you might increase the failure chance from 0% to 50% on a single roll.

[deljzc]

On a side not about Acrobatics/Athletics... Man_Over_Games....

Have you ever had decided to do a combined check for an action? So you add their Acrobat AND Athletics and made a DC 35 or something and make them roll 2d20?

This turns the roll into a bell curve so the players have a greater chance of success but sometimes I think what the players are trying to do is BOTH Athletic AND Acrobatic? This is instead of the penalty of making them check BOTH Athletics and Acrobatics separate (which is what we talk about with too many die rolls making the chances of success exponentially harder).

Thanks.

[Man_Over_Game]

On a side not about Acrobatics/Athletics... Man_Over_Games....

Have you ever had decided to do a combined check for an action? So you add their Acrobat AND Athletics and made a DC 35 or something and make them roll 2d20?

This turns the roll into a bell curve so the players have a greater chance of success but sometimes I think what the players are trying to do is BOTH Athletic AND Acrobatic? This is instead of the penalty of making them check BOTH Athletics and Acrobatics separate (which is what we talk about with too many die rolls making the chances of success exponentially harder).

Thanks.

Kinda!

I do a number of weird things but one I do, that the books recommend, is having players pick what proficiencies they want to use towards a particular problem. If they then provide two different proficiencies towards the problem, they make the roll with Advantage.

Having the players pick what proficiencies they use, after the DM determines what Ability score to use, is actually in the Player's Handbook. Players just have skipped over it so much that it sounds like a houserule.

Having the players roll advantage when they can apply two different skills to a single problem is a houserule suggested in Xanathar's.

I just do both.

For example, I have the party stumble upon a murder scene at a crossroads in the middle of the forest. The destroyed wagon has blood on it, and something cleanly slashed through the front wheels of the cart.

A player wants to investigate further. Rather than telling him what skill he must use, I tell him to make an Intelligence check. He says he wants to apply his proficiencies in Investigation, Nature and Medicine.

I ask why he wants to use Nature and Medicine, and he responds that he wants to get clues off of the blood to guess how long ago the cart was attacked, as well as determine what kind of race the driver was. Nature doesn't apply here, but Medicine does.

I agree that his action is sensible, so I have him make the Intelligence roll, using his proficiency bonus, with Advantage. Since the roll HAS to use Intelligence (because the DM believes Intelligence is the most applicable for this situation), and Proficiency is the same across all skills, it doesn't really matter what skills he actually uses for the roll, just how many are applicable.


If it's 1 skill, ability score + proficiency.
If it's 2 or more skills, ability score + proficiency + Advantage.
If it's 0 skills, ability score.
If 1 or more skills have Expertise, double the proficiency bonus


This allows your players to use their skills as often as they want to, rather than only as often as you say they can. Coincidentally, this fixes all of the problems we've been saying for years regarding Medicine and Nature checks, as well as rewarding players for having redundant proficiencies (like being proficient in Persuasion and Deception, or Athletics and Acrobatics).

[deljzc]

Kinda!

I do a number of weird things but one I do, that the books recommend, is having players pick what proficiencies they want to use towards a particular problem. If they then provide two different proficiencies towards the problem, they make the roll with Advantage.

Having the players pick what proficiencies they use, after the DM determines what Ability score to use, is actually in the Player's Handbook. Players just have skipped over it so much that it sounds like a houserule.

Having the players roll advantage when they can apply two different skills to a single problem is a houserule suggested in Xanathar's.

I just do both.

For example, I have the party stumble upon a murder scene at a crossroads in the middle of the forest. The destroyed wagon has blood on it, and something cleanly slashed through the front wheels of the cart.

A player wants to investigate further. Rather than telling him what skill he must use, I tell him to make an Intelligence check. He says he wants to apply his proficiencies in Investigation, Nature and Medicine.

I ask why he wants to use Nature and Medicine, and he responds that he wants to get clues off of the blood to guess how long ago the cart was attacked, as well as determine what kind of race the driver was. Nature doesn't apply here, but Medicine does.

I agree that his action is sensible, so I have him make the Intelligence roll, using his proficiency bonus, with Advantage. Since the roll HAS to use Intelligence (because the DM believes Intelligence is the most applicable for this situation), and Proficiency is the same across all skills, it doesn't really matter what skills he actually uses for the roll, just how many are applicable.


If it's 1 skill, ability score + proficiency.
If it's 2 or more skills, ability score + proficiency + Advantage.
If it's 0 skills, ability score.
If 1 or more skills have Expertise, double the proficiency bonus


This allows your players to use their skills as often as they want to, rather than only as often as you say they can. Coincidentally, this fixes all of the problems we've been saying for years regarding Medicine and Nature checks, as well as rewarding players for having redundant proficiencies (like being proficient in Persuasion and Deception, or Athletics and Acrobatics).

I like this a lot. I often wondered at the "redundant" proficiencies and that's where the whole "add them together, create a new DC and then check" type of logic came from (knowing that it is flawed however).

[prabe]

Kinda!

I do a number of weird things but one I do, that the books recommend, is having players pick what proficiencies they want to use towards a particular problem. If they then provide two different proficiencies towards the problem, they make the roll with Advantage.

Having the players pick what proficiencies they use, after the DM determines what Ability score to use, is actually in the Player's Handbook. Players just have skipped over it so much that it sounds like a houserule.

Having the players roll advantage when they can apply two different skills to a single problem is a houserule suggested in Xanathar's.

I just do both.

For example, I have the party stumble upon a murder scene at a crossroads in the middle of the forest. The destroyed wagon has blood on it, and something cleanly slashed through the front wheels of the cart.

A player wants to investigate further. Rather than telling him what skill he must use, I tell him to make an Intelligence check. He says he wants to apply his proficiencies in Investigation, Nature and Medicine.

I ask why he wants to use Nature and Medicine, and he responds that he wants to get clues off of the blood to guess how long ago the cart was attacked, as well as determine what kind of race the driver was. Nature doesn't apply here, but Medicine does.

I agree that his action is sensible, so I have him make the Intelligence roll, using his proficiency bonus, with Advantage. Since the roll HAS to use Intelligence (because the DM believes Intelligence is the most applicable for this situation), and Proficiency is the same across all skills, it doesn't really matter what skills he actually uses for the roll, just how many are applicable.


If it's 1 skill, ability score + proficiency.
If it's 2 or more skills, ability score + proficiency + Advantage.
If it's 0 skills, ability score.
If 1 or more skills have Expertise, double the proficiency bonus


This allows your players to use their skills as often as they want to, rather than only as often as you say they can. Coincidentally, this fixes all of the problems we've been saying for years regarding Medicine and Nature checks, as well as rewarding players for having redundant proficiencies (like being proficient in Persuasion and Deception, or Athletics and Acrobatics).

I do more or less this, exactly, in my campaigns, at least as far as allowing proficiency in two skills to equal advantage. It just seemed to make sense. I should probably formalize it more, at some point. Looks as though I'll have time on my hands ...

[kazaryu]

To be Hidden, a creature must take the Hide action against all non-allied creatures that currently know where you are. If a Rogue runs behind a building and takes the Hide action, he rolls against the highest enemy Passive Perception who knew where he was. THAT'S who he's trying to hide from, and he's Hidden if he succeeds.
A Hidden creature:

Needs to be Unseen to initiate being Hidden
Is Hidden until:
A creature spots him by gaining obvious vision or by making a successful contested Perception check against the Hidden Creature.
The Hidden creature does an action that would reveal them (like attacking or casting a spell).
Is considered Unseen/Unheard while they're appropriately Hidden (that is, a creature is effectively invisible/silent indefinitely until something causes them not to be)



to expand on the bolded slightly, because i think its important to note. RaW, that check takes an action. its the 'search' action. DM's are obviously free to rule it how they want, but generally it shouldn't (imo) be 'oh there's a hidden person. all enemies of that person make a perception check, for free, on their turn to spot it'. That approach is contrary to RaW and is a serious nerf to stealth mechanics (which disproportionately affects the class that is overall one of the weakest in combat)

[djreynolds]

Passive perception, IMO only works outside of combat. And that means you're not reading a map or whatever

Once actions are taken, then initiative is rolled. And it takes an action to perceive.

Now if the said rogue uses an action that would break his hiding, such as attacking someone... now the rogue is no longer hidden.

[Keravath]

Passive perception, IMO only works outside of combat. And that means you're not reading a map or whatever

Once actions are taken, then initiative is rolled. And it takes an action to perceive.

Now if the said rogue uses an action that would break his hiding, such as attacking someone... now the rogue is no longer hidden.

Just a quick point .. the entire definition of passive perception in the PHB is that it does not require a search action.

"Passive Perception. When you hide, there's a chance someone will notice you even if they aren't searching. To determine whether such a creature notices you, the DM compares your Dexterity (Stealth) check with that creature's passive Wisdom (Perception) score, which equals 10 + the creature's Wisdom modifier, as well as any other bonuses or penalties. If the creature has advantage, add 5. For disadvantage, subtract 5."

If a rogue tries to hide in combat using the bonus action hide then their success or failure is determined by comparing their stealth roll to the passive perception of the opponents in the combat.

[Man_Over_Game]

Just a quick point .. the entire definition of passive perception in the PHB is that it does not require a search action.

"Passive Perception. When you hide, there's a chance someone will notice you even if they aren't searching. To determine whether such a creature notices you, the DM compares your Dexterity (Stealth) check with that creature's passive Wisdom (Perception) score, which equals 10 + the creature's Wisdom modifier, as well as any other bonuses or penalties. If the creature has advantage, add 5. For disadvantage, subtract 5."

If a rogue tries to hide in combat using the bonus action hide then their success or failure is determined by comparing their stealth roll to the passive perception of the opponents in the combat.

Well said. It's important to note that this is the only real mention of Passive skills in the entire game to be mentioned in the middle of combat. This is likely because you're trying to change an enemy's condition (a contested check) but it's not something the creature is actively doing (so he doesn't get a roll).

Consider Saving Throws, which involve using a static number that the enemy rolls against to resist a condition upon themselves.

Hiding from a creature is really just about causing a status effect on yourself, so the situation is reversed: The enemy uses a static value, which you roll against.

If there was another means of inflicting a status condition on yourself that an enemy might passively prevent (such as an anti-magic field from an enemy), I'd imagine it'd work the same way where the character rolls to successfully gain his status condition.

Creatures should only roll for things that they are actively choosing or reacting to. That applies to more than just Stealth, but Stealth is a good way of showing what I mean.

[Keravath]

Surprise:
"The DM determines who might be surprised. If neither side tries to be stealthy, they automatically notice each other. Otherwise, the DM compares the Dexterity (Stealth) checks of anyone hiding with the passive Wisdom (Perception) score of each creature on the opposing side. Any character or monster that doesn't notice a threat is surprised at the start of the encounter.
If you're surprised, you can't move or take an action on your first turn of the combat, and you can't take a reaction until that turn ends. A member of a group can be surprised even if the other members aren't."

Surprise is generally hard to achieve in 5e except perhaps for a rogue operating alone who has expertise in stealth AND something to hide behind.

In order to surprise someone you have to be successfully hidden.

Hiding:
"You can't hide from a creature that can see you, and if you make noise (such as shouting a warning or knocking over a vase), you give away your position. An invisible creature can't be seen, so it can always try to hide. Signs of its passage might still be noticed, however, and it still has to stay quiet."

Things to keep in mind.

1) If an opponent could see the character then they can not be hidden. For example, an alert guard, on guard duty, looking around them, WILL see any one who tries to approach them if they are visible. A rogue doesn't get a free roll to sneak up on the guard. The rogue doesn't get to hide where the guard can see. If there was a plan and someone distracted the guard sufficiently to stop them from looking around then the rogue might be able to sneak up on them (DMs discretion). However, this would NOT usually constitute surprise since whatever was used to distract the guard might well have alerted them to a threat.

2) Surprise requires that the player successfully hide AND the target to be unaware of ANY threats. For example, a very alert guard who is really paying attention may be impossible to surprise even if the player succeeded on a stealth check. This would be because the guard is expecting something even if they did not notice the specific threat.

3) This is also why rogues might try to go in by themselves since if the whole party goes in, everyone rolls stealth checks and if even one party member is noticed by a specific defender then they are not surprised by anyone. The character or monster only needs to see a single threat, not any specific threat to void the surprise condition. Surprise only happens if the defender is caught completely unaware of an impending threat.

[Man_Over_Game]

In order to surprise someone you have to be successfully hidden.


I disagree:

Surprise:
"The DM determines who might be surprised..."

It's worth noting that that's the first line in the Surprise rules. Everything else comes after.

I think that Hiding is the most appropriate way of Surprising a creature, which is why it's mentioned directly with the Surprise rules, but I don't think it should be a requirement. Smashing through a door at full speed (bonus points if Silence is cast on your side of the door?) would be a very good way of surprising a group of unsuspecting badguys, as would using something like Dimension Door.

The reason I think this is necessary to point out is because isolating Surprise to be a Stealth mechanic makes it become a rules-specific situation. The DM is no longer empowered to consider Surprise mechanics, since there are already rules for that.

If more DMs used their gut instead of the rulebook, fewer players would have had bad experiences with the Assassin Rogue. If you could use a Sleight of Hand + Deception check to stab someone in the throat before they could think, without skulking in the middle of the street, you'll end up with a skill system that feels more Assassin's Creed than Skyrim.




Personally, I think Surprise is something that should be used regularly. It rewards those who work hard, punishes those who are careless, and what about that is bad in a game? I think the only real reason Surprise shouldn't be regularly used is if either:

Both sides are not doing anything to hide their approach (two war parties).
One side is hiding, but was actively found by someone looking for a threat (like a guard).

If a Fighter wants to Hide in his plate armor, and the enemy side is lazy and didn't post a guard, he's Hidden until someone actively looks for something. It's enough of a gamble as-is, since anyone on guard duty would be able to spot him, so make it worth the risk.

[djreynolds]

Keravath is right, "unless someone is actively searching, Stealth is opposed by a passive wisdom (perception)" Sage Advice.

[Man_Over_Game]

Keravath is right, "unless someone is actively searching, Stealth is opposed by a passive wisdom (perception)" Sage Advice.

But what do you roll when nobody's there to contest it?

We have this...idea that you "save" your initial Stealth roll, and then you keep it until something, passive or active, manages to beat it. That is, if you Hide while nobody else is around, and then enter a war zone, anyone who has a Passive Perception higher than your Stealth roll automatically knows where you are, as soon as they'd be able to detect you. Almost like a Detect Magic aura against you.

This is stupid, for two reasons:

1. Nowhere else in the game does it mention utilizing a unique roll value rounds after you have rolled. Even in an attempt to break a grapple, attempting to break after the initial attempt results in a new roll on both sides. It's not that you're "Grappled against a 20-point Athletics", but that you're "Grappled". The condition is set, but breaking it has its own rules.

2. It's double dipping. Not only do you have to successfully beat everyone's average roll, but you also have to beat any additional rolls that they may make to spot you. Hiding costs an Action, so why is that countered by a random passerby who doesn't even spend a Reaction or Bonus Action to spot you? This puts a major cost on Action economy, making Not Hiding almost always better than Hiding. A similar example is seen with Counterspell vs. Any Spell Targeted by Counterspell (that is, the one casting Counterspell always comes out ahead, and the only losing move is to not have Counterspell).

Yes, you need permission to take the Hide Action to roll your Dexterity (Stealth) check to determine if you're successfully Hidden. But once that happens, you're Hidden until determined otherwise. You don't need additional permission to Hide just because some people walked by during their conversation. Their Passive Perception isn't relevant, because you're not rolling against it. You're already Hidden, so if you're not rolling, and they're not rolling, what contest is there to make?

What the Sage Advice is referring to is trying to Hide while a creature knows where you are. You only take the Hide action to initiate the Hidden condition, not to maintain it. If you Hide while nobody is there to contest it, you'll obviously succeed, and you'll continue to be Hidden until something rolls against you, you take an action that would reveal yourself to a creature, or something makes Hiding impossible.

[djreynolds]

If you think about combat, I guess at this point your backside is puckered up and you are paying attention and I guess its why you can only be surprised in the first turn of combat

Passive perception is actually pretty powerful... its like you rolled a 10. It makes the observant feat very strong in battle

Hiding has been a huge discussion here forever. I think it is really hotly debated because it is confusing

I mean if you are actively fighting and getting attacked, are you at disadvantage for your passive perception check? Because a rogue at this time can step in and sneak attack you

Lets take this rogue for example, they need advantage or an ally within 5ft to sneak attack.

An orc is fighting off a goliath barbarian who recklessly attacking him, the barbarian's halfling buddy doesn't even need to hide to gain advantage to sneak attack because the ally is distracting that enemy at that moment the rogue has a "pseudo" advantage to sneak attack

But 10ft away is another orc, so the halfling uses his cunning action and hides in the barbarian's frame and rolls a stealth check and beats the contested orcs passive perception, moves 10ft and cannot only sneak attack this orc but will also get advantage on the attack

But what if that orc is taking the dodge action, he gets disadvantage on vs opponents he can see but unfortunately doesn't get any bonus to his passive perception check. And because he's dodging cannot use his action to search.

Hiding in combat becomes such a huge amount of work... that it sucks.

But lets say during this combat their is another rogue who has never revealed themselves, and has beaten all of the passive perception checks and has quietly skirted the battlefield in the shadows... why can't they surprise anyone?

I mean if the orcs are fighting 4 PCs for 4 rounds, and then all of a sudden out pops an assassin... I'm sure one of them would be surprised when he gets his throat slit.

[Tanarii]

But what do you roll when nobody's there to contest it?

We have this...idea that you "save" your initial Stealth roll, and then you keep it until something, passive or active, manages to beat it. That is, if you Hide while nobody else is around, and then enter a war zone, anyone who has a Passive Perception higher than your Stealth roll automatically knows where you are, as soon as they'd be able to detect you. Almost like a Detect Magic aura against you.

Actually, the rule is you save the roll and it is contested by perception roll of anyone that actively searches for you.

PHB sidebar on Hiding, page 177:
When you try to hide, make a Dexterity (Stealth) check. Until you are discovered or you stop hiding, that check's total is contested by the Wisdom (Perception) check of any creature that actively searches for signs of your presence.

This is not a combat specific use of the skill. It's a general rule for the use of the skill. The combat specific use is an action to make the roll against your check.

Edit: oops should have kept reading. The idea that the saved roll is compared to passive comes from the section further down. But I'll note, in furtherance of your argument, that it doesn't say this comparison still happens after the initial attempt to hide. But that's a reasonable inference that you're supposed to, based on the initial statement above.

Passive Perception. When you hide, there's a chance someone will notice you even ifthey aren't searching. To determine whether such a creature notices you, the DM compares your Dexterity (Stealth) check with that creature's passive Wisdom (Perception) score, which equals 10 + the creature's Wisdom modifier, as well as any other bonuses or penalties.

[Man_Over_Game]

Actually, the rule is you save the roll and it is contested by perception roll of anyone that actively searches for you.

PHB sidebar on Hiding, page 177:
When you try to hide, make a Dexterity (Stealth) check. Until you are discovered or you stop hiding, that check's total is contested by the Wisdom (Perception) check of any creature that actively searches for signs of your presence.

You're right about that being evidence of saving the initial roll. It bugs me that I missed that in the books.

I dispute that the saved roll interacts with Passive Perception, though, as this passage mentions "actively searches for signs of your presence", and the second passage states "When you hide, there's a chance someone will notice you even if they aren't searching."

I interpret that as:

Take the Hide Action. If creatures knew where you were, roll against their Passive Perception, as they can notice you even while not searching for you. If they actively search for you with the Search Action, they roll against your previous Stealth check total.

There's no reference to determine when a creature would passively check against your already-successful Hide action, which is really the most difficult thing to keep open-ended. Is 30 feet acceptable? 10? 100? Does it scale off of your Passive Perception? Not only that, but that's not even implied to be something a DM needs to decide, where the Surprise rules state that the DM determines who is Surprised.

It could be confirmation bias, and that I'm reading it wrong because I want it to be wrong, but it feels difficult to interpret that Passive Perception is to be checked against a saved Stealth Check total at....whenever. Even if it included things like "When the Hidden creature could be seen", as a creature could fail a Hide Action even when Unseen by failing to roll above a creature's Passive Perception. But there's no sense of timing or guidance on it, even for the DM.

[deljzc]

Can someone explain surprise exactly with the number of dice you actually roll?

Just make an example and how/when you roll.

I mean it seems the confusion lies in three different vocabulary words and how they interact with each other:

Stealth ("Stealthy")
Hide (Hidden)
Surprise

And how these three vocabulary words interact both out of combat (without strict turn/timing) and in combat (with very strict turn/timing).

I understand that surprise is only a "condition" that exists in the FIRST ROUND OF COMBAT but obviously, stealth and hidden seem to exist BEFORE and DURING combat (well, stealth probably doesn't exist during combat but stealth checks do... i.e. hiding).

But as we talk about this, I'm somewhat confuse with who is rolling dice and how many. Especially with a group of monsters trying to be stealthy/hidden as they encounter the PC's.

[Man_Over_Game]

To make it short:

Rogue takes the Hide Action (as a Bonus Action because of their feature)
Rogue makes his Dexterity (Stealth) roll, rolling it against the highest Passive Perception of the creatures that he is hiding from (that is, all creatures that know where he currently is).
If he succeeds, he's Hidden. While Hidden, he's also Unseen.
If, for some reason, something causes him to no longer be Hidden (which can be from him attacking, or simply just stepping into an enemy's view), all creatures that can know of his location, do.

If a creature wants to look for a Hidden Creature, they take the Search Action. They roll their Wisdom (Perception) check, contested with the Rogue's previous Stealth total. If the Perception check wins, the Rogue is found.

For the sake of groups, I'd just have the most restrictive circumstances of the group roll. That is, the creature with the lowest Stealth rolls against the creature with the highest Passive Perception, and vice-versa.

With this interpretation, someone that is Hidden generally remains Hidden until a creature actively searches for them (that is, the searcher takes the Search Action and rolls dice). Unless that happens, or something else causes the Hidden creature to be revealed, the Hidden creature generally makes no additional rolls and isn't contested to remain Hidden.

Another interpretation is that every possible creature that could detect you uses their Passive Perception contested against your saved Stealth Check total. If you get within the circumstance allowed for a creature to detect you, your Stealth Check is immediately checked against their Passive Perception, and you are revealed if theirs is higher.


As for how Surprise is done, use the saved Stealth roll you're using and compare it to the Passive Perception of each enemy creature when you roll Initiative. Each enemy creature that fails this diceless check is Surprised.

----------

For example, Fighter & Company try to sneak up to these bandits, but the Fighter's plate armor gives him only a 9 on his total. He isn't spotted until someone posts a lookout, and thankfully the bandits don't.

The players initiate their attack once they're near the hostages, and the DM calls for Initiative. Any enemy creature with a Passive Perception of 8 or less fails to prepare for the invading party and is Surprised.

You only roll dice when someone takes the Hide Action, or when someone takes the Search Action. Everything else happens automatically.

[Segev]

I would generally run with the saved stealth roll, myself, but I would also have little problem, if it got forgotten for some reason, just rerolling it. If it's been long enough that it's been forgotten, chances are circumstances have changed enough that your stealth efforts may be yielding different results.

The risk of abuse here is a player (including the DM, but since DMs can just cheat, this is usually less of an issue) rolling poorly, conveniently "Forgetting" the roll, and then saying, "Oops, guess I have to roll again," in hopes that they do better when actually confronted by things that might spot him.

That said, if a stealthy PC or party are moving about, I probably would make them roll a new Stealth check each time they come across a group of people they want to sneak past. They've been moving about, and the circumstances of their stealth have changed.

Even in combat, from round to round, if a sneaky character is hiding and not revealing himself, but somebody is actively looking for him, I might make both sides roll, unless the sneaky hider has managed to not move around or do much but stay hidden. I'd also allow somebody doing that much to try to hide to keep rerolling their Hide check and keep any rolls that are better, on the grounds that they're "digging in" and working the hiding spot.

[deljzc]

So Man...

So how to you check if the PC's are surprised exactly?

Do you take the entire group of monsters (assuming they are trying to be "stealthy" or "hidden") and then roll d20 and add the modifier of the LOWEST of the group of monsters?

Let's say I roll a 12 and I have a group of monsters with some dex +1, others with dex +3, etc.

My roll would then be 12 +1 = 13.

And ANY PC with a passive perception of 13 or higher is NOT surprised. And any PC with a passive perception of 12 or lower is surprised?

Is that correct?

If a group of monsters is "hidden", is there a check before combat starts to see if the characters SEE the hidden monsters first, before combat and surprise? Or does that roll kind of all happen at once.

[Man_Over_Game]

So Man...

So how to you check if the PC's are surprised exactly?

Do you take the entire group of monsters (assuming they are trying to be "stealthy" or "hidden") and then roll d20 and add the modifier of the LOWEST of the group of monsters?

Let's say I roll a 12 and I have a group of monsters with some dex +1, others with dex +3, etc.

My roll would then be 12 +1 = 13.

And ANY PC with a passive perception of 13 or higher is NOT surprised. And any PC with a passive perception of 12 or lower is surprised?

Is that correct?

If a group of monsters is "hidden", is there a check before combat starts to see if the characters SEE the hidden monsters first, before surprise? Or does that roll kind of all happen at once.

That is correct.

On your second bit, no. It's implied that as soon as the monsters intend to attack, Initiative is rolled, Perception is checked against Stealth, and then you handle things as the numbers line up.

So half of your players could be surprised, while the other half heard a slight tang of metal and reacted on their warrior's instinct. Initiative is an abstraction of what actually happens. Even if a player manages to go first in the Initiative order while not being Surprised, it is treated that he recognized the threat before they initiated their attack.

Picture a scene in Star Wars or Lord of the Rings. Would it be out of place for Legolas or Han Solo to shoot a hidden enemy before everything goes to sh**?

If you're concerned about an enemy approaching in melee combat to attack an unsuspecting player, you could have that enemy make another Hide Action against the players when that enemy would reasonably be revealed (like stepping out into the open to approach the players from behind).

DMs naturally have enemy parties post lookouts to avoid this sort of problem. It'd make sense that a party of adventurers should do the same.

[deljzc]

I've always understood SOME of the party could be surprised and others not.

I am just trying to understand the mechanics in terms of rolls and results and what exactly to compare (and what modifiers are involved).

You do roll only once for an entire group on surprise, both for monsters vs. the PC's Passive Perception and vice versa, correct?

And you take the LOWEST Dex (Stealth) modifier in that group. That is the roll you use.

And instead of having each player (or monster) roll to see if they are surprised using the Passive (Wisdom), the game streamlines it by making the comparison a static "passive perception" fixed number.

So every surprise at the beginning of combat, we are really only talking ONE ROLL. You can't think of situations where you are rolling for multiple things going on during the surprise check?

[Keravath]

I disagree:

It's worth noting that that's the first line in the Surprise rules. Everything else comes after.

I think that Hiding is the most appropriate way of Surprising a creature, which is why it's mentioned directly with the Surprise rules, but I don't think it should be a requirement. Smashing through a door at full speed (bonus points if Silence is cast on your side of the door?) would be a very good way of surprising a group of unsuspecting badguys, as would using something like Dimension Door.

The reason I think this is necessary to point out is because isolating Surprise to be a Stealth mechanic makes it become a rules-specific situation. The DM is no longer empowered to consider Surprise mechanics, since there are already rules for that.

If more DMs used their gut instead of the rulebook, fewer players would have had bad experiences with the Assassin Rogue. If you could use a Sleight of Hand + Deception check to stab someone in the throat before they could think, without skulking in the middle of the street, you'll end up with a skill system that feels more Assassin's Creed than Skyrim.




Personally, I think Surprise is something that should be used regularly. It rewards those who work hard, punishes those who are careless, and what about that is bad in a game? I think the only real reason Surprise shouldn't be regularly used is if either:

Both sides are not doing anything to hide their approach (two war parties).
One side is hiding, but was actively found by someone looking for a threat (like a guard).

If a Fighter wants to Hide in his plate armor, and the enemy side is lazy and didn't post a guard, he's Hidden until someone actively looks for something. It's enough of a gamble as-is, since anyone on guard duty would be able to spot him, so make it worth the risk.


I agree with you that ultimately determining surprise is up to the DM.

However, I'd like to point out that the rules specifically state that the DM doesn't need to ask for a skill check in situations where success is assured.

In your example of breaking down the door in a silence spell. If the people in the room didn't notice the door opening, the wind from the event, dust or pieces of door flying around, the fact that part of the room suddenly isn't reflecting sound from the walls (if someone cast a silence spell on the door side of a room where folks are talking then they would likely notice the sudden lack of an echo - have you ever been in an anechoic room? - the difference is noticeable - whether they would figure out what is wrong is a different story), no one happened to be looking in the direction of the door or caught the motion out of the corner of their eye then they could be surprised. However, bashing in a door takes time, if the folks in the room notice it happening then they won't be surprised.

But ... the characters outside the door are intrinsically hidden. If they are unseen and unheard by the folks in the room then the DM can simply say they are hidden since a die roll for the skill check isn't required.

In your dimension door example, the same applies. If the characters are unseen and unheard from where they cast the spell then the odds are good that they will surprise whoever is in the location when they pop in. They were intrinsically hidden before they took the action that revealed themselves to their opponents so it is up to the DM whether those opponents are surprised. If the opponents happened to be using a scrying spell and were keeping track of the characters ... then they would not be hidden and the creatures wouldn't be surprised.

The rules also state that a creature that does not notice a threat is surprised. Hiding is the most common way for a threat not to be noticed. However, if the characters are trusted and are not considered a threat then when they turn around and attack ... the opponent is going to be surprised since they did not perceive a threat.

The same goes for the other examples you list. If the target perceives a threat then they are not surprised. If they do not perceive a threat then they will be surprised.
"Any character or monster that doesn't notice a threat is surprised at the start of the encounter."

It is up to the DM to determine whether a threat is perceived at the start of an encounter by one or both sides. This is completely dependent on the circumstances and is most commonly resolved using stealth vs perception checks but that certainly isn't the only way.

[Man_Over_Game]

I've always understood SOME of the party could be surprised and others not.

I am just trying to understand the mechanics in terms of rolls and results and what exactly to compare (and what modifiers are involved).

You do roll only once for an entire group on surprise, both for monsters vs. the PC's Passive Perception and vice versa, correct?

And you take the LOWEST Dex (Stealth) modifier in that group. That is the roll you use.

And instead of having each player (or monster) roll to see if they are surprised using the Passive (Wisdom), the game streamlines it by making the comparison a static "passive perception" fixed number.

So every surprise at the beginning of combat, we are really only talking ONE ROLL. You can't think of situations where you are rolling for multiple things going on during the surprise check?

Ah, sorry. That's mostly correct.

You only roll once, for the group who's Hiding, using that group's lowest Stealth value (probably the Paladin, or their equivalent of one). I suppose you could roll everyone's and just use the lowest, but that's a lot of excess work for no gain.

Compare that value to everyone's Passive Perception. Since everyone's Passive Perception is just your Perception Bonus and +/- 5 for Dis/Advantage, it's pretty easy to determine who's Surprised and who's not.

The idea is, you're only Surprised when you didn't know there was a threat. If you found out there was a Paladin skulking about, you'll know there's a threat. It doesn't matter if you don't know where the others are, you just know that you need to fight right now.

Technically, the Paladin's allies could all still be Hidden while all of their enemies aren't Surprised. That's a little more awkward, but I'd just keep them all Hidden until an enemy uses the Search Action or until they're revealed in an obvious method, like normal. Just because you know it's an ambush doesn't mean you know where the enemies are coming from, and having a round of attacks against you with Advantage is a lot better than that AND doing nothing for your first round. The Hidden party still hid up to that point, and would reveal themselves as soon as anyone looked for them or if they ran out into the open, so they still get some benefit from Hiding before combat.


Or, to summarize:

When combat starts, the least-stealthy creature in the hidden party is either revealed or stays hidden. He stays hidden if the entire enemy party is Surprised. Otherwise, only that one creature is revealed, and all creatures that spotted him are not Surprised.

If the enemy creatures want to spot the rest of the party (and they can't see the rest of the hidden party, for whatever reason), they'd have to take the Search Action. Personally, I just compare it based on the Passive value of their Stealth Skill by that point, since the players' individual rolls weren't tracked. It's pretty easy to ask "Does anybody have a Passive Stealth of 16 or less?" and just call those players out as no longer being Hidden.

Since Advantage/Disadvantage is already accounted for in Passive Perception as a +/- 5 change, any special circumstances you'd apply as the DM are already considered. I guess it could get complicated with determining who has the lowest Stealth bonus if part of the party has Advantage while the other half has a higher bonus, but I'd roll using the stats of the creature that had Advantage with a lower bonus, since Advantage usually requires some kind of resource or circumstance that the players should let go to waste.

[deljzc]

I agree with you that ultimately determining surprise is up to the DM.

However, I'd like to point out that the rules specifically state that the DM doesn't need to ask for a skill check in situations where success is assured.

In your example of breaking down the door in a silence spell. If the people in the room didn't notice the door opening, the wind from the event, dust or pieces of door flying around, the fact that part of the room suddenly isn't reflecting sound from the walls (if someone cast a silence spell on the door side of a room where folks are talking then they would likely notice the sudden lack of an echo - have you ever been in an anechoic room? - the difference is noticeable - whether they would figure out what is wrong is a different story), no one happened to be looking in the direction of the door or caught the motion out of the corner of their eye then they could be surprised. However, bashing in a door takes time, if the folks in the room notice it happening then they won't be surprised.

But ... the characters outside the door are intrinsically hidden. If they are unseen and unheard by the folks in the room then the DM can simply say they are hidden since a die roll for the skill check isn't required.

In your dimension door example, the same applies. If the characters are unseen and unheard from where they cast the spell then the odds are good that they will surprise whoever is in the location when they pop in. They were intrinsically hidden before they took the action that revealed themselves to their opponents so it is up to the DM whether those opponents are surprised. If the opponents happened to be using a scrying spell and were keeping track of the characters ... then they would not be hidden and the creatures wouldn't be surprised.

The rules also state that a creature that does not notice a threat is surprised. Hiding is the most common way for a threat not to be noticed. However, if the characters are trusted and are not considered a threat then when they turn around and attack ... the opponent is going to be surprised since they did not perceive a threat.

The same goes for the other examples you list. If the target perceives a threat then they are not surprised. If they do not perceive a threat then they will be surprised.
"Any character or monster that doesn't notice a threat is surprised at the start of the encounter."

It is up to the DM to determine whether a threat is perceived at the start of an encounter by one or both sides. This is completely dependent on the circumstances and is most commonly resolved using stealth vs perception checks but that certainly isn't the only way.


This is another tricky thing I asked a long time ago that I had trouble wrapping my head around.

There is a part in the Sinister Secret of Saltmarsh where the party finds a "prisoner" but he is really a plant who's goal is to disrupt the party and eventually likely attack (with surprise if possible).

I had the same confusing questions back then. If all the players kind of know this guy is shady, do they "perceive the threat" when he tries to attack or is there the potential for surprise.

I mean, the NPC bad guy wouldn't attack if he felt the PC's were onto his act, but at the same time, I don't want to just tell the party (who around the table have said, "We're keeping an eye on the guy").... I rolled a 15 on surprise and you are all surprised (because 1st level PC's don't have that high of passive perception). That would likely piss some players off.

This whole thing is tricky for me to understand EXACTLY how to implement consistently. Because what is good for the goose is good for the gander. The rules I make for how PC's surprise monsters has to be somewhat consistent with how monsters surprice PC's.

This can be as simple as how you run the opening encounter in Philander to as simple as a Lurker on the ceiling of a typical 15'x15' dungeon room.

[Man_Over_Game]

This is another tricky thing I asked a long time ago that I had trouble wrapping my head around.

There is a part in the Sinister Secret of Saltmarsh where the party finds a "prisoner" but he is really a plant who's goal is to disrupt the party and eventually likely attack (with surprise if possible).

I had the same confusing questions back then. If all the players kind of know this guy is shady, do they "perceive the threat" when he tries to attack or is there the potential for surprise.

I mean, the NPC bad guy wouldn't attack if he felt the PC's were onto his act, but at the same time, I don't want to just tell the party (who around the table have said, "We're keeping an eye on the guy").... I rolled a 15 on surprise and you are all surprised (because 1st level PC's don't have that high of passive perception). That would likely piss some players off.

This whole thing is tricky for me to understand EXACTLY how to implement consistently. Because what is good for the goose is good for the gander. The rules I make for how PC's surprise monsters has to be somewhat consistent with how monsters surprice PC's.

This can be as simple as how you run the opening encounter in Philander to as simple as a Lurker on the ceiling of a typical 15'x15' dungeon room.

That's a very valid point. My personal use of it is to treat Surprise as a "trigger" of initiative. Like a Reaction, in a way.

In your example of the prisoner, he'd likely attack when the party was distracted, like if they engage in combat with another target. If the party is keeping an eye on their 'hostage' there's no way for him to take the Hide action to be subtle enough to strike. When Initiative starts, and the players are getting ready for what they presume to be a normal encounter with some goblins, the prisoner "strikes", Surprising the party members who failed to consider the threat behind them. In a way, the Prisoner has the priority of starting "initiative", since he was planning to attack long before the goblins or Players did.

Heck, you could Surprise everyone, even the goblins, and it'd work out fine! Surprise is better used as an extension of the Initiative system, rather than an extension of Stealth. When someone would have acted sooner than someone else, and neither side was fighting, consider Surprise.



Personally, I allow my players to do more than just Dexterity (Stealth) for a Hide Action. Deception or Sleight of Hand seem to be very relevant, as long as you're not trying to make yourself "Unseen". The same mechanics for Surprise would work just fine regardless of what skills you decided to use to determine it. But that's a houserule, and not something supported with anything in the books.


If your players had someone keeping an eye on their prisoner, it'd simply follow the same rules as someone Hiding under less-than-ideal circumstances. They either cannot Hide (like if their actions were clearly visible), or they get Disadvantage (because the DM decided that their attempt to Hide was possible but especially difficult).

[Segev]

Yeah, all surprise means is that whoever is doing the surprising has kicked off a fight when nobody was expecting it. In Man_Over_Game's example, the surprise is only a matter of moments, but it's enough that the treachery gives the guy a round to act while everyone else is shaking off that surprise.

One thing that I've had to wrap my head around, and seen others have difficulty with, is the notion that the guy who gets the jump on everyone acts really late in the initiative round. That is, Bob the Traitor suddenly reveals his true colors and tries to backstab Sally the Sorceress, but he rolls a 4 on initiative while Sally gets a 20.

The whole deal with Surprise as a condition is that, yes, Sally has taken her first turn long (in initiative order) before Bob gets to stab her. But all she did was shake off Surprise; Bob still gets to stab her before she can take an act against him.

In a sense, what taking an action to shake off Surprise represents is that some people will be able to take reactions, or otherwise defend themselves adequately as they quickly adjust to the situation. They still aren't acting before Bob, but Bob didn't move fast or stealthy or whatever enough to catch them entirely flat-footed. (Not that "flat-footed" is a game term in 5e; I mean it in the usual common language sense.)

If you read in a story that the narrator notices some surprising bit of treachery happening too fast for him to stop it, but he's able to (for example) just barely dodge out of the way of it, he's stopped being Surprised before the malefactor acted, but the malefactor WAS already in the process of doing stuff and got that stuff done before the narrator could do anything more than defend himself from it.