D&D 5E Adjudicating "bursting in"

[ExploderWizard]

Whatever you do, whenever the PCs bust down the door and rush in, make sure this is playing.

http://www.televisiontunes.com/Star_Trek_-_Amok_Fight_Scene.html

 

[Al2O3]

In the Starter Set adventure (Lost Mines of Phandelver) there is one room with guards off duty playing dice. It is explicit in the adventure that if characters burst in the enemy is surprised. Seems like what you've been doing too. And since hearing the dice requires a check while listening at the door I would say even discussing tactics slowly before entering should work without alerting those inside.

 

[FormerlyHemlock]

I'm sure this has been covered at some point but my forum search came up empty, so apologies in advance if this is a duplicate.

Anyway - my PCs love to burst into rooms to give them an element of surprise. However this kind of "surprise" is not covered in the rules that I can see.

The last time this happened I rolled a dice to see how many of the occupants were actually surprised but that seemed a bit lame. Any suggestions on how to improve my adjudication of moments like this?

This is an artifact of the initiative system you're using. If you switch to a WEGO system like AD&D initiative, it's easily dealt with as follows:

* If the enemy was genuinely relaxing (code white) and didn't hear the PCs coming, they are surprised.
* If the enemy was on alert to potential danger (e.g. guards in a guard room), but didn't hear the PCs coming, they are not surprised but act as if they had taken the Delay action implicitly, which means they automatically lose initiative, but get a separate declare/act cycle after all the PCs finish acting.

Note that if in case #2 the enemies choose to Delay on following rounds as well, it winds up identical to side initiative: all the PCs act, then all the enemies, then all the PCs, then all the enemies, etc. But if on the following rounds the enemies attempt to be faster than the PCs ("guard #1 tries to run away before anyone can grapple him") then it gets resolved with an initiative contest.

 

[Guest 6801328]

I agree with requiring stealth rolls and comparing to passive perception. Failing doesn't have to mean that they are discovered, just that the occupants of the room say, "Huh? What was that noise?" and thus aren't surprised when the door bursts open.

But....

Depending on how big the doors are and how big your party is, it seems a little unlikely that they are all going to file in one at a time and get a free attack before the bad guys get to do anything. If you wanted to get fancy you could house-rule something where you do an opposed roll, and for each point the PCs win by, one character gets a surprise attack. Have them determine their marching order before they make the roll, to simulate them not knowing how many will get through in time.

EDIT: Another variant would be have everybody roll their Initiative, and anybody who beats the monsters gets a surprise attack. Then start normal combat at the top of the order. You could combine this with the required Stealth roll, if you wanted to mitigate the effectiveness of "bursting in".

 

[I'm A Banana]

One thing I've starting doing (and will be using continuously now for CoS) is having PCs use 'Passive Stealth'.

Rather than having each PC make a DEX (Stealth) check just prior to them busting through a door (which then begs my question on if they actually TRIED to be stealthy, or didn't declare they were trying to Hide etc.)... I instead have all PCs record their 'Passive Stealth', which is 10 + DEX mod + Prof bonus (if they have Stealth) - 5 (for Disadvantage due to armor if applicable.) I treat this as their perpetual "We're walking carefully throughout the dungeon trying not to make any noise" check. I then compare this to the Passive Perceptions of any monster they come across who aren't actually alert or on guard. Any monster whose PP is higher than the loudest PC is not surprised, those who are lower are. By the same token, if the monsters are not doing anything purposefully loud (which would automatically be determined by me as being noticed by the party), then they also will have Passive Stealth checks that the party will check their Passive Perception against. So when the door is flung open, any PC or monster whose PP is higher than the lowest PS of someone else in the opposing group, that creature is not surprised and gets to act during the first round of combat.

Does that hose the really stealthy PCs? Yes and no. Technically, it doesn't matter how stealthy the best PCs are, because all that matters is that the group of goblins heard ONE of the PCs coming, and thus knew to jump up and grab weapons. For the stealthy PCs... it's only if they break out ahead of the rest of the party to scout do they get to make active DEX (Stealth) checks and roll the d20 to determine their really high DC for the goblin's passive perceptions (and thus quite likely get to take the entire group of monsters by surprise.) The only downside of course being that if they take that shot, they're out ahead of their party and have to deal with a round or two of the fight just being with them. So maybe it's worth it to do so for that free round of attacks with surprise... maybe it's not (if they don't think they can withstand all the return attacks.)

By the same token... the same way stealthy PCs can scout ahead and thus make active Stealth checks... any creature who is "on guard" or alert and searching for danger gets to make active Perception checks to hear the party coming (1d20 + INT + Prof bonus). So they have a 50% chance of getting a higher check over their standard PP. But this only applies to those creatures on guard and not to the rest of the monsters-- unless of course the PCs diddle-daddle and give the guard monster time to alert his friends that someone is coming.

Thus far Passive Stealth has been working well, as it gives me a constant baseline for how loud the party is as they walk normally throughout the dungeon. Makes checking them nice and easy.

It's interesting because I kind of do the inversion.

Rather than "passive Stealth" I use passive Perception for the watch, and have the PC's roll stealth. One of the things this does: because Hiding is an action, it means that a PC can move up to their speed and Hide, but they can't move while hiding. This means that things like guard patrols and the like are easier to pull off. Roll init for everyone: on the PC's turn, they can move up to their speed, and if they find a place to hide, they can take the Hide action. On the NPC's turn, maybe they move down the corridor on patrol or spend the round chatting with their buds or something. This creates a bit of give-and-take and also means that there's a bit of a "timer" on your stealth - sooner or later, you might roll low, and that means that the enemies will hear you.

This stops surprise from being a dominant strategy, but still something worth pulling off.

 

[FormerlyHemlock]

It's interesting because I kind of do the inversion.

Rather than "passive Stealth" I use passive Perception for the watch, and have the PC's roll stealth. One of the things this does: because Hiding is an action, it means that a PC can move up to their speed and Hide, but they can't move while hiding. This means that things like guard patrols and the like are easier to pull off. Roll init for everyone: on the PC's turn, they can move up to their speed, and if they find a place to hide, they can take the Hide action. On the NPC's turn, maybe they move down the corridor on patrol or spend the round chatting with their buds or something. This creates a bit of give-and-take and also means that there's a bit of a "timer" on your stealth - sooner or later, you might roll low, and that means that the enemies will hear you.

This stops surprise from being a dominant strategy, but still something worth pulling off.

I don't understand this sentence as an implication of actions. In 5E, you can spend movement before and/or after an action. The PHB calls this out explicitly for attacks. I can't remember if it is explicit for actions other than attacks, but it's certainly never said that movement and actions happen in different phases or anything.

 

[ExploderWizard]

I don't understand this sentence as an implication of actions. In 5E, you can spend movement before and/or after an action. The PHB calls this out explicitly for attacks. I can't remember if it is explicit for actions other than attacks, but it's certainly never said that movement and actions happen in different phases or anything.

It isn't so much a rules issue as a common sense issue. If you move 15', crouch behind a barrel and hide, then move another 15', how are you still hidden? You WERE hidden very briefly before leaving your spot.

 

[Uller]

It is reasonable for the PCs to surprise monsters in this case unless there is some reason why the monsters may have heard the PCs approach the door (such as one monster is alert or has some sort of heightened senses). I always require a stealth check, often against disadvantage passive perception...clumsy, heavily armored PCs have blown it on a few occasions.

However, monsters should react in a reasonable manner. If you're a guard sitting in your guard room playing dice or snoozing or whatever because NOTHING has happened in the last 6 months then suddenly 4 murder hobos burst in and kill 2 of your comrades before you can even grab a weapon, what are you going to do? Fight them toe-to-toe at a tremendous disadvantage or run down the hall and alert everyone else to the danger? Even the noise of combat should have some chance of alerting someone...especially spells or other effects that do thunder damage and the like...It should not be an easy thing for a party to sneak through the dungeon and gain surprise on every encounter.

Also, we modified the surprise rules for my game mainly because as written the surprise rules leave open the possibility of one side getting to act twice before the other side can act once. The way I explained it to my players: "do you want it to be possible for a high damage monster to get two rounds of attacks on you if you get jumped?". So basically we added the "surprised" condition:

- attacks against you have advantage
- you have disadvantage on DEX saving throws
- you cannot take reactions
- on your turn, start of turn effects take place then you are no longer surprised and your initiative is moved to the end of the queue
- once your turn comes up again, only new start of turn effects take place, you take your turn then all end of turn effects take place

So let's say PCs A B C and D surprise monster Z. Everyone rolls init normally (so high dex critters are good at becoming unsurprised). Init order ends up being
A B Z C D.

A and B both have advantage on attacks on Z and Z has disadvantage on dex saves during their turn and can't take any reactions. On it's turn Z is no longer surprised but new init order becomes A B C D Z but C and D do not get advantage then Z gets it's normal turn and combat progresses from there.

 

[Saeviomagy]

I pick which side rolls by the heuristic "which side should have randomness applied to them".

For the "burst into the room" I take a passive group stealth check (with modifications to avoid the even/odd problems of group checks) and roll perception for the monsters: it seems to me that some monsters should be surprised and others not surprised. Which of the PCs is detected doesn't matter at all.

For general "avoid detection" sneaking around, I'll take a rolled group stealth check vs passive monster perception to indicate if roomfuls of monsters are disturbed. Monsters will either investigate or not, and the degree of the investigation depends on how well the check goes overall.

For specific "sneak past this guard" scenarios, it's individual stealth checks vs passive perceptions. Once alert, the guards can spend actions to make rolled perception checks against existing stealth checks.

 

[FormerlyHemlock]

It isn't so much a rules issue as a common sense issue. If you move 15', crouch behind a barrel and hide, then move another 15', how are you still hidden? You WERE hidden very briefly before leaving your spot.

That makes sense, which is why I said "I don't understand this sentence as an implication of actions," emphasis added. The second half the sentence makes sense to me in isolation, just not in relation to the bit about actions and passive stealth.

This way of running Stealth is very reasonable (make the player say how specifically they are hiding) but doesn't intersect at all with either passive vs. active or hiding as an action. It would work exactly the same way even if Hiding were free as part of movement AND Stealth were passive instead of active. But Kami--I mean, I'm A Banana connected the three ideas, so clearly he's got something additional in mind that I'm not getting.

I typically play "Hidden" as a way of making your enemy lose track of your location during combat. So if you crouch behind the barrel briefly and Hide, then scoot, a successful Stealth roll means your opponent (watching out of the corner of his eye as he observes the whole battlefield) has lost track of your location and thinks you're still behind the barrel.