Group hide and seek

Question

How should one manage a group trying to elude detection by another group in D&D 5e?

For a one-on-one situation, stealth opposed to perception works well. However, if everyone rolls stealth/perception, the seekers' top roll will often exceed the hiders' worst roll, making it impossible for the hiders to succeed if the two groups are large (e.g. 10 hiders and 10 seekers).

A group check for the hiders seems like a reasonable solution in a passive perception case (i.e. if at least half the hiders beat the top seeker's passive perception, they elude the seekers). However, I don't know how this would work if the seekers were actively searching. There do not seem to be any rules for "opposed group checks".

My intuition suggests that in a hide and seek situation, the hiders' job becomes harder as their group size grows, while the seekers' job becomes easier as their numbers grow.

Answer 1

Seekers

People on watch for eight hours or so are not hyper-vigilant all the time - they chat, warm their hands at the fire, go for a leak etc. Unless there is some reason that seekers are actively looking for the hiders (e.g. a recent alarm) then this should be a passive Wisdom (Perception) check so in effect the hiders are rolling against a fixed (but unknown) DC.

If there are multiple seekers then they should us the Working Together rules on p. 175 of the PHB; this gives advantage to the person with the best Wisdom (Perception), +5 on passive or 2 rolls on active checks. Don't forget that there are lots of ways that this advantage can be cancelled: dim light being the most often overlooked.

Hiders

The needs of your scenario should dictate if you use group checks or not. That is, is it more interesting/fun for the characters to succeed or fail as a group or individuals.

Group checks (PHB p.175) make things much easier for the hiders. For example, for 4 characters all needing to roll an 11 or more a group check will result in success 68.75% of the time whereas individual checks will have no one detected only 6.25% of the time (http://anydice.com/program/8892). Notwithstanding, bigger groups make both more difficult, however, for group checks it is a slow decline while individual checks fall off a cliff.

Helping someone sneak is problematic, I can see arguments both ways. Obviously, calling out instructions would be counter productive but relying on others to watch the guards while you only watch for their hand signals would really help. My personal feeling is if the players can tell you how teamwork gives them advantage then let them have that advantage. (I am assuming that it is usually the players that are hiding, not the monsters).

Answer 2

Group Check vs. Teamwork

The NPCs set the DC with a Wisdom (Perception) check of the most perceptive NPC who rolls with advantage—as per the working together rules on PH 175.

The PCs then use that DC for their group check. Unless, of course, you want each PC to pass/fail on their own merit, then it's individual checks vs the same DC as set above. This would allow the rogue to continue on even if the paladin is discovered. That being said, if the paladin is discovered, the security might just be heightened due to the fact that "where there is one, there is many."

Answer 3

My simple, flavorful method . . .

is to use the standard rules for Advantage/Disadvantage, but change the dice routine just a little to add some narrative flavor.

For the Searchers, I ask the character with the best roll to make their Perception, and then I ask for a second roll to represent the party's "helping". Mechanically, this is simply granting Advantage for the help, but narratively it allows for another character to get the credit for the good roll.

Similarly, the Hiders make two rolls, with the best Stealth to roll, and another roll made for the rest of the party to represent the Disadvantage of hiding multiple bodies. Again, this makes it more clear just who is to blame when the party is discovered.

Personally, unless there is a clear reason not to, I allow the party to apply the best character's bonuses. This represents the sort of coaching from the expert that you would expect in such situations. An argument could be made that for the Hiders, the worst character should make the roll, but I personally consider that to be punitive - I prefer to err on the side of character competence rather than incompetence.

Answer 4

"the seekers' top roll will often exceed the hiders' worst roll"

True, but isn't this the way one would expect this to work in real life? If 10 people are looking for 10 other people, it is EXTREMELY unlikely none of those 10 'hiders' will be discovered. This is why stealth operations favor smaller-than-regulation squads in RL operations.

That said, just because one hider is spotted, does not mean the whole group is then caught. At that point it becomes a job for the spotted's liar-skills to cover for those still hidden.

As for your closing intuition, it again makes sense. Extreme example would be: You can't hide a parade, especially not from another parade.

Answer 5

I think your intuition is right: if there are more seekers, there are more chances to find a hider. And if there are more hiders then there are also more chances to find a hider.

The checks should reflect that fact.

Hiders

Normally I would say that each hider succeeds or fails on their own merits, meaning an individual Stealth check. That is how it would work in real life: in the children's game, hide and seek, the seekers find the hiders one at a time, not all together as a group. Back in the world of D&D, if the seekers don't know there are any hiders but then discover one, they would be alerted to the possibility of further hiders; so they should now get advantage or a small numerical bonus to their Perception checks (I favour +2).

I would make one exception to this ruling: if a party are hiding in situ (ie they are not moving) and they have been doing so for at least a minute, I would allow a group Stealth check as the stealthier members help the less stealthy to be inconspicuous. So long as they stay still, the less stealthy members have much less chance of mucking things up for the party.

Seekers

Seekers can benefit from the most advantageous kind of check: a teamwork Perception check, which gives a bonus to the check of the creature with the best modifier. But this doesn't come cheap in combat. It requires the use of the Search action by the lead creature and the Help action by one other creature. That's only two seekers, so what are the rest of them doing? I'd be inclined to give a +1 bonus for each additional seeker - but to what limit I don't know!

When the seekers are relying on passive Perception I'd use the passive Perception of the lead creature and be done with it. The +5 from advantage granted by a single helper is way too strong. I could see an argument for a +1 bonus for each additional seeker as suggested in my previous paragraph.

The DM may also want to think about what different seekers can perceive based on their senses and their position in the environment (eg the hiders may have obscurement and cover from some seekers, but only obscurement from others).