D&D 5E Perception in 5e, discuss how it works

[Sadrik]

What if you roll actively for Perception and have a lower result than your passive perception?

For example when the group is in marching order and they've let you know that they want to watch for traps.

I think this is an excellent reason to not use anything but passive perception. Then apply the +5 for advantage and -5 for disadvantage to represent hardship - rather than a crap or great roll. Also there still is randomness on the other side of the equation...

 

[ren1999]

Let me explain the mechanics and see if you all agree with my interpretation.

A DM notes 2 players with a wisdom modifier of +2 and a wisdom modifier of -1.

He writes;

Player 1 Passive Perception 10+2=12. Player 1 has the Perception skill so that is wis mod+2+proficiency bonus for 1st level+2=wis(Perception)+4

Player 2 Passive Perception 10-1=9

Player 1 says she is actively looking for attackers.
The DM has her roll a wis(Perception) check 1d20+4=12+4=16
The DM then rolls a dex(Stealth) check of 1d20+3=15+3=18.
So Player 1 does not perceive the assassin sneaking up on Player 2.

After, no player says they are actively looking.
The DM secretly rolls a dex(Stealth) check of 1d20+3=12+3=15.
He compares the 15 to the passive perceptions of 12 and 9.
Both players are surprised.

In what other situations would we use Perception, with examples?

 

[77IM]

Two phenomena from the Starter Set adventure that I think are worth noting (this is from memory so I may be slightly wrong):

1) For a lot of secret doors, it says you con find them with a passive Wisdom (Perception) of 15, or by actively making a Wisdom (Perception) check vs. DC 10. This means it is substantially easier to find doors by active searching -- the passive score only kicks in when you've already got at least an 80% chance of succeeding with an active search.

I think that's really awesome -- it keeps active checks meaningful; lets you roll less than your passive score and still succeed; and it lets the passive score handle checks so easy it's not worth rolling.

2) There were a few places (I think) where you could roll a more specialized skill, or you could just use Wisdom (Perception) but the DC was higher. Like I think one of the early pit traps could be spotted with Wisdom (Survival) DC 10 or Wisdom (Perception) DC 15, or something.

In general I like that. I think skill overlap is totally fine. I'd rather keep the game moving and allow PCs to do stuff than spend time agonizing over exactly which skill to use.

 

[Verys Arkon]

I've noticed that a lot of the traps and secret doors in the Lost Mines of Phandelver have different DCs for passive perception and active perception, as well.

 

[Li Shenron]

What if you roll actively for Perception and have a lower result than your passive perception?

Maybe it's better not to think too much about a narrative explanation for passive checks. In 3e, Take10 had a narrative explanation, but it's that which sometimes caused debatable results. If you see it only as a rule variant, that you choose for meta-reasons (e.g. I don't want to let the players know there's something to listen/see, I don't want to roll too many dice, I don't want too much swinginess of the result...) then it can be more acceptable.

 

[Psikerlord#]

I think passive checks are an antifun mechanic, and ought not be used at all. There was no such thing in 2e or earlier, and no such thing in many other games. Just roll the dice when you need a check. All passive does is give you a 10 on the roll, its pointless, esp if coupled with "you can only try once unless something changes" rule (eg to stop players saying "I keep searching till I roll20" etc). The "I dont want to tip my players off to the ambush/trap" etc argument is also unpersuasive, as you are about to hit them with the trap etc, so just get them to roll... whats it matter? By using passive perception you reduce the randomness and end up with the same pc spotting everything all the time, which is lame for multiple reasons. I wont be using passive perception in our games.

I agree that it appears theres lots of cross over between perception and investigation, and that the skills are poorly explained and somewhat confusing. Perception is already the A++ skill however, so if investigation can get some love, good.[CHARGE][/CHARGE]

 

[mach1.9pants]

I may well be playing things a bit differently too. I like the Perception/Search split. In which Perception is your subconscious ability to see something. Search is actually getting involved with the environment to find things. And they'll have different DCs. Perceiving there is a key under the mat in the first glance around the room is going to be hard, searching the room it is going to be very easy. This will be tied to if the player says 'I will look under the mat' which is automatic.

So you'll be allowed a subconscious check, DM rolls if there is something to be seen, you can also do one more check as an action. No more unless something changes. e.g. Open the door, Perception Check at Stealth DC to spot hidden goblin. They cannot use Perception to see the false bottom of the table drawer. Player says 'I pause at the door and have a good look' (action, another roll to see goblin). Now no matter how long he stares at the room he doesn't get another roll - unless something changes, for example the goblin moves. If they want to go in a Search, they will auto find the goblin (although Search takes longer so they'll get surprised by the gobbo) but must roll to find the false bottom, unless a players specifies searching for it.

 

[nnms]

My solution to this whole issue is to concentrate on the core of game play.

1) DM describes situation
2) Players describe what their characters do.
3) DM describes results and the new situation

So if there's a trap on the ground and they declare that they are just walking right up the corridor, I'll take into consideration how well hidden it is and how perceptive they are and go from there. I'll like use something like the passive skill thing to figure it out, but if I feel it's uncertain I'll do what the game text recommends and go to the dice.

Similarly if there is a desk in a room with a key in a drawer and the player says their character is searching the desk thoroughly, I'm going to assume they are opening the drawers and will discover all the content of those drawers without needing to make an investigation roll.

And if the real thing to be found is a button on the wall behind the desk but they don't say they are pulling the desk away from the wall or looking down behind it, they have no chance of finding the button. In this type of situation if someone says they are searching the desk thoroughly, I'll ask for more info and give them the opportunity to expand that such a search means flipping the desk over, breaking it apart or looking behind it.

My take of the rules text is that it's trying to appeal to a couple different approaches at once. It seems to want to cover both the description heavy approach and the ability to summarize or skip over the details and just rely on a roll at the same time. "I search the desk" could mean that how thorough you are depends on how high you roll rather than what you declare your characters as doing, or it could mean that you just look at the surface and open a drawer or two with no roll needed.

 

[Tony Vargas]

I think passive checks are an antifun mechanic, and ought not be used at all. There was no such thing in 2e or earlier, and no such thing in many other games.

In classic D&D, instead of checking passive perception, the DM would roll a 'secret' check behind the DM screen to see if the players noticed something. The idea was to keep it secret so, if they failed, they wouldn't be aware that there was something to miss. Some DMs went as far as rolling dice behind the screen or calling for meaningless checks just to keep players from assuming 'something was going on' because they heard dice rolling or were asked for a roll.

The DM noting passive perception and checking against it seems a pretty reasonable way of doing the same thing without so many meta-game issues.

 

[Psikerlord#]

In classic D&D, instead of checking passive perception, the DM would roll a 'secret' check behind the DM screen to see if the players noticed something. The idea was to keep it secret so, if they failed, they wouldn't be aware that there was something to miss. Some DMs went as far as rolling dice behind the screen or calling for meaningless checks just to keep players from assuming 'something was going on' because they heard dice rolling or were asked for a roll.

The DM noting passive perception and checking against it seems a pretty reasonable way of doing the same thing without so many meta-game issues.

Yes I think rolling behind the screen is better. Also getting pcs to make 10 perception rolls pre session and using those (randomly selected). either of those is better than "take 10" on perception checks.