D&D 5E Rolling for Passive Perception

[el-remmen]

I use passive perception for “happening to notice something” (even if you weren’t specifically looking for it) like someone hiding, and rolls for perception when a character makes an action declaration about looking. I thought this was how it was supposed to work and even if it isn’t, it works for me.

I don’t use passive investigation because I can’t wrap my mind around how one investigates passively.

 

[BookTenTiger]

I use passive perception for “happening to notice something” (even if you weren’t specifically looking for it) like someone hiding, and rolls for perception when a character makes an action declaration about looking. I thought this was how it was supposed to work and even if it isn’t, it works for me.

I don’t use passive investigation because I can’t wrap my mind around how one investigates passively.

You sit in your armchair with a hunting cap and pipe and give amusing remarks to your companion, Dr. Watson.

 

[iserith]

I don’t use passive investigation because I can’t wrap my mind around how one investigates passively.

Some traps can be noticed by making deductions based on clues in the environment in addition to or instead of noticing a trap by sight, sound, smell, etc. So instead of passive Perception while the PCs are traveling the dungeon searching for traps along the way, the DM can instead use passive Investigation.

 

[ezo]

So what do you think? Am I crazy?

Maybe I missed it, but what are you rolling to get the bonus for the door, trap, etc.?

Because choosing how you roll sort of defines what your expectations are of the game world. While having a random element is a neat idea, I wonder how much impact it will ultimately have...

For myself, if I used such a system, I would probably roll 2d6-2, giving me a range of +0 to +10, average +5, which would be the equivalent to DC 10, 15, and 20 as min, avg, and max.

I really like @BookTenTiger's idea, because I hate passive scores and this saves time. I can roll the passive bonus and compare to the Passive scores of the PCs, rather than have 4 players roll against a set DC.

This would, IMO, also be really the prime benefit. As DM, I can have all the Wisdom (Perception) modifiers for the PCs on hand, and when something comes up I can roll for the "something" compared to their modifiers, instead of asking all of them to roll.

I don’t use passive investigation because I can’t wrap my mind around how one investigates passively.

Yeah, this is a good way of putting what our games sort of do. Perception is passive, Investigation is active.

 

[Hriston]

As it is, I use Passive Perception in two ways:

1) When a character enters a setting, they perceived everything their Passive Perception would allow: hidden creatures, treasures, etc. Usually for secret doors and traps I give big clues and invite the character to look closer.

2) When a character rolls a Perception check, their Passive Perception is their floor- the lowest result they can get. If they roll below their Passive Perception, I just use their Passive Perception.

This does, however, make adventure design a little weird.

I think the weirdness is coming from a few things. First, I think your "1)" above encompasses too many types of hidden information. I would only check the passive Perception of a character that is looking for the specific type of thing that's hidden. So if a player says their character is going to look out for hidden danger while the party travels through the environment, then I would check their passive Perception to detect traps and monsters, but only if they're in a position to perceive those things, like in the front rank or something. If they say they're doing something else, like looking for hidden treasure or secret doors, then they would have no chance to notice hidden traps or monsters while traveling and might be surprised by any monsters.

Second, to address your "2)", Wisdom (Perception) check results below the passive Perception score should be possible. A passive check should only be used when a character performs a task repeatedly or when the DM wants to make a check secretly. In all other situations, a rolled check should be used and the result should stand on its own.

For example, in next week's adventure the characters are going to enter a dungeon room with a trap: a net will fall, and two flying swords will attack.

If I set the DC of spotting the net at, say, 14, I just know two characters will see the net. Why put a net there at all in that case? If I set it at 18 then no one will see it, but is that realistic? And why use Passive Perception at all if I'm just going to juice all the DCs?

First, what are the characters doing to notice the net and the flying swords? Are they keeping watch for hidden threats, or are the otherwise occupied? Are they at the front of the group as they enter the room, or are they in the back? Once you know the player's answers to these questions, you'll know whether they have a chance to notice the trap and the hidden monsters and about how difficult it will be. If they have a chance, check their passive Perception scores against whatever DC you've decided to notice the net. Make a Dexterity check for the flying swords and compare the passive Perception score of anyone who has chance to see if they notice them. Anyone who isn't staying alert for danger or is in a disadvantageous position doesn't notice the net and is surprised by the swords. I think this works quite well.

 

[Charlaquin]

I use passive perception for “happening to notice something” (even if you weren’t specifically looking for it) like someone hiding, and rolls for perception when a character makes an action declaration about looking. I thought this was how it was supposed to work and even if it isn’t, it works for me.

It’s not, by my reading, what the PHB actually says to do, but it is, in my experience, how the vast majority of DMs do it. The PHB says to use passive checks to represent the average result of an action performed repeatedly over time. So, they’re less passive checks and more ongoing action checks. I think most DMs figure, “being aware of your surroundings” is an action you’re always performing, so keeping passive Perception up at all times makes sense enough.

 

[ezo]

Yeah, the term "Passive" for Passive Perception is very misleading IMO.

It is used for two things, RAW:

1. Using it when making repeated checks is inconvenient as a PC performs a check over and over.
2. When the DM wants the result of a Perception check to be "secret". I.e. the DM assumes the player's roll is a 10.

"Passive" is being used in the sense that the player doesn't roll. Calling it "Repeated or Secret Checks" would be more appropriate IMO. As others have mentioned, it is sort of like the old "Take 10" option.

Anyway, use #1 above is the common usage IME. A PC is paying attention, looking around for any danger or strange things, etc. so the default roll of constant Wisdom (Perception) checks is a 10 + modifiers.

Personally, I find this somewhat interesting because, in cases like uses of Stealth, for instance, typically the DM has the player roll once and use just that roll versus all opposing Passive Perceptions unless the situation changes. Why doesn't the DM just use a Passive Stealth, as the idea of repeated Dexterity (Stealth) checks would likely be more reasonable than a single check.

After all, it moves into meta-gaming when a player rolls a Stealth check and gets low, the player knows the PC might be found out. But, the roll doesn't necessarily mean the PC knows they "screwed up" and put in a bad performance... Unless they REALLY screw up, the PC should always think they are being stealthy, shouldn't they?

 

[iserith]

Personally, I find this somewhat interesting because, in cases like uses of Stealth, for instance, typically the DM has the player roll once and use just that roll versus all opposing Passive Perceptions unless the situation changes. Why doesn't the DM just use a Passive Stealth, as the idea of repeated Dexterity (Stealth) checks would likely be more reasonable than a single check.

The DM certainly can, and I have in cases where the monsters have been lying in wait for a while. Compare passive Stealth to passive Perception and determine surprise.

After all, it moves into meta-gaming when a player rolls a Stealth check and gets low, the player knows the PC might be found out. But, the roll doesn't necessarily mean the PC knows they "screwed up" and put in a bad performance... Unless they REALLY screw up, the PC should always think they are being stealthy, shouldn't they?

In cases like this, the issue is the DM called for the check when it didn't yet matter. Ask for the roll only when there's something to be resolved (i.e. there's something that's watching for danger and the outcome of that is uncertain with a meaningful consequence for failure).

 

[CreamCloud0]

personally the difference in investigation and perception to me is that Perception is to notice something that for lack of a better term is 'already visible'(though it could relate to any sense) but perhaps not immediately obvious while Investigation is to uncover and search out additional information that is concealed or requires a level of active interaction to discover.

perception to notice the persistant quiet tapping, investigation to learn where it's coming from or that it's morse code
perception to notice the unusual wearing on the desk's edges, investigation to find out what caused it (or how to open the hidden compartment if that's why)