D&D 5E I don't use Passive Perception

[Rya.Reisender]

I'd say, not all active rolls require the use of an action. For example recalling what you know is something I'd make an active roll (if result not already clear from context), even though it doesn't require an action. Whether something requires an action or not I make depend on how long it takes to do. If it takes a significant portion of 6 seconds, then it requires an action. Yes, I'd include looking around here.

Anyway, when determining a passive check, such as passive Perception, if there is nothing preventing you from taking the time to succeed, then I use your capability instead of your passive score. This applies to all passive scores.

That seems like a bad idea. You're basically increasing all passive values by 10, meaning for you almost everything is a success given enough time.

The whole point of the passive score is that it applies when you have unlimited time. The active roll is simply the luck factor.
Like if you try to break a door then you roll actively first. If lower than DC, then you fail, otherwise you succeed. If you failed, you can keep trying to break it open, but you won't roll again, instead the passive score applies, so it's either success after a certain time or never succeeds.

 

[iserith]

That seems like a bad idea. You're basically increasing all passive values by 10, meaning for you almost everything is a success given enough time.

The whole point of the passive score is that it applies when you have unlimited time. The active roll is simply the luck factor.
Like if you try to break a door then you roll actively first. If lower than DC, then you fail, otherwise you succeed. If you failed, you can keep trying to break it open, but you won't roll again, instead the passive score applies, so it's either success after a certain time or never succeeds.

I wouldn't say that's the "whole point" of a passive score.

Passive checks are used to resolve uncertainty in a task that is being performed repeatedly. That is only after uncertainty is established by the DM per the standard adjudication process. If spending a lot of time on a single task removes uncertainty as to the outcome in the DM's judgment, then there is no ability check, passive or otherwise, only a result. This is in the DMG, page 237.

 

[cooperjer]

An interesting thought came up in Wednesday AL Princes of the Apocalypse when a PC acquires the earth temple war pick that grants tremor sense 60-ft. The PC wants to get a strong understanding of how many NPCs are behind a door or down a curvy hallway. I had the player roll a perception check. In this case the environment was dimly lit by glowing crystals, so it was a roll at disadvantage. A few questions came to my mind regarding that scenario:

1. Why is the PC at disadvantage due to dim light?
a. The PH indicates this is the rule.
b. In this case the PC can now sense motion through the ground as easily as it can see motion through space.
c. How does dim light grant disadvantage if there are two senses (tremor sense & hearing) working to detect a location of a creature?

2. Would using passive tremor sense be like using passive visual sense?
a. If one can sense motion past a wall is it not enough that a passive sense of that motion would also indicate how many creatures there are, and their relative distance to you?

3. How long does it take to become accustomed to acquiring a new sense?
a. Would using the new sense be at disadvantage for some time until the user became accustomed to it?
b. Can the new sense be used passively if the character is not accustomed to it?

I feel that it's appropriate to have the player roll to determine the number of creatures, approximate distance, and size category, and even if some are in stone armor. I feel that a tremor sense passive perception will let the player know if creatures are present and if there are a few, several, or a crowd. It would also let a player know if there is a significantly large creature in the room. I feel that dim light is not applicable to using tremor sense and thus rolls would not be at disadvantage. However, in this case the PC was within 60-ft of a large waterfall and thus I feel the waterfall vibration would cause disadvantage.

How would you use a new sense in passive perception?

 

[Edward Centofante]

As a player, I get frustrated by active perception checks. Invariably we've had a PC or even two in the group that has specialized in perception and is at the front of the party leading us through a dungeon and traps just come out of nowhere because we didn't say "I'm searching for traps" in the last 15 seconds.

And while that's irritating, sometimes it's not a big issue. A pitfall trap or something that gives that lead PC a few saves (dex save then an acrobatics check) to avoid damage. But other times it's some massive contraption (like that wave machine thing early in LMoP) that nails the whole party and it's just like... "Ok, so my character keeping watching didn't see any of these gears, ropes, or pulleys needed to set off something like this?" and the DM's response is "You didn't say you were checking for traps in this particular part of the hallway".

 

[robus]

1. Why is the PC at disadvantage due to dim light?
a. The PH indicates this is the rule.
b. In this case the PC can now sense motion through the ground as easily as it can see motion through space.
c. How does dim light grant disadvantage if there are two senses (tremor sense & hearing) working to detect a location of a creature?

Seeing as tremorsense is light independent it should not impact the perception. Which PHB page/rule are you referring to?

2. Would using passive tremor sense be like using passive visual sense?
a. If one can sense motion past a wall is it not enough that a passive sense of that motion would also indicate how many creatures there are, and their relative distance to you?

I don't know if it would be quite as clear. It would be like listening to noises and trying to determine the number of creatures making the noise. Vibrations (and sounds) have a tendency to merge together, amplifying somethings and quietening others. So the roll would determine how precise the perception is IMHO.

3. How long does it take to become accustomed to acquiring a new sense?
a. Would using the new sense be at disadvantage for some time until the user became accustomed to it?
b. Can the new sense be used passively if the character is not accustomed to it?

Excellent question! I'd say that the player would definitely have disadvantage on their rolls while they were getting to grips with this new capability. Next time they level up I'd say they'd gained enough experience to use it effectively.

I feel that it's appropriate to have the player roll to determine the number of creatures, approximate distance, and size category, and even if some are in stone armor. I feel that a tremor sense passive perception will let the player know if creatures are present and if there are a few, several, or a crowd. It would also let a player know if there is a significantly large creature in the room. I feel that dim light is not applicable to using tremor sense and thus rolls would not be at disadvantage. However, in this case the PC was within 60-ft of a large waterfall and thus I feel the waterfall vibration would cause disadvantage.

How would you use a new sense in passive perception?

For passive perception I'd say that the player (and accompanying party members) would need to be still in order for there to be no false positives. Otherwise it would be just like keeping watch by listening or seeing? If there's any vibration source nearby (dwarven forge, waterfall etc) then it would be at disadvantage just as you say.

 

[robus]

As a player, I get frustrated by active perception checks. Invariably we've had a PC or even two in the group that has specialized in perception and is at the front of the party leading us through a dungeon and traps just come out of nowhere because we didn't say "I'm searching for traps" in the last 15 seconds.

This is exactly the issue that passive perception is intended to address! You declare the ongoing/repetitive action your character is performing while navigating the dungeon: looking for traps, watching out for monsters, mapping, scanning for secret doors. The DM should be using those numbers to determine whether the characters find what they're looking for. See earlier in the thread for options of making that more fun than just comparing two static numbers.

And while that's irritating, sometimes it's not a big issue. A pitfall trap or something that gives that lead PC a few saves (dex save then an acrobatics check) to avoid damage. But other times it's some massive contraption (like that wave machine thing early in LMoP) that nails the whole party and it's just like... "Ok, so my character keeping watching didn't see any of these gears, ropes, or pulleys needed to set off something like this?" and the DM's response is "You didn't say you were checking for traps in this particular part of the hallway".

DM is not using passive perception correctly IMHO. You don't have to keep declaring the action you're doing repeatedly. You just say I'm keeping watch for traps and your PP does the rest.

But as for the goblin hideout with the flood, that is triggered by goblins keeping watch. Yeah that was a bit of a gotcha as it's triggered by the lookouts not by any mechanism you can interfere with... But the DM could have telegraphed that the walls are slimy allowing you to infer that the water level occasionally gets very deep. Also there are saving throws to hang on (climb up) to avoid the flood IIRC?

 

[Satyrn]

DM is not using passive perception correctly IMHO. You don't have to keep declaring the action you're doing repeatedly. You just say I'm keeping watch for traps and your PP does the rest.

I think it's more appropriate to say that DM is just trying to play gotcha! against his players. His players think they're performing an ongoing sweep of the area, but theDM isn't letting them.


See, the thing about passive perception is this: It never needs to be used. Not even for repeated tasks. PP is just an option for tables that don't want to roll dice to decide the outcome of those repeated tasks. There are other solutions, too. A common one I see suggested on the boards is to make a list of prerolled checks for the DM to consult as needed.



When I run DM, when something comes up that the repeated task deals with, I ask for a roll instead of using the passive score. I'd rather have dice rolled because it's more fun for the my group.

But they still totally get to search for traps without restating it every 5 minutes.

 

[iserith]

As a player, I get frustrated by active perception checks. Invariably we've had a PC or even two in the group that has specialized in perception and is at the front of the party leading us through a dungeon and traps just come out of nowhere because we didn't say "I'm searching for traps" in the last 15 seconds.

DM Fail in my view. He or she wants to let a trap go off more than validate your previous choices. It's possible it comes from a good place - the DM thinks it would be exciting and memorable to have the PCs deal with a trap in motion right now, for example. But I think ultimately when it comes to my well-laid plans versus the players' agency, I'm siding with the players Every. Single. Time.

 

[ro]

The Passive Perception calculation is 10 + perception modifier. This is way too good. Why should the average PC with Perception proficiency and +1 Wisdom be automatically noticing everything DC 13 or better at level one?

With Observant, this jumps up to DC 18 at level one for a variant human. If the PC actually cares about wisdom, it can easily be DC 20.

But DCs are supposed to mean:
DC 5 : Very Easy
DC 10 : Easy
DC 15 : Medium
DC 20 : Hard
DC 25 : Very Hard

So a level one PC, without trying, sees everything that is "Hard" to see? No way. And a normal one sees nearly everything Medium.

A Normal, everyday non-perceptive fellow should probably notice very easy. Someone with Perception maybe Easy. Someone with Observant, Medium.

Normal PC, +0 Wisdom : Very Easy DC 5
Perceptive PC, +3 Wisdom +2 Proficiency : Easy DC 10
Observant PC. +3 Wisdom, +5 Observant +2 Proficiency : Medium DC 15

A regular passive skill check is then 5 + prof + mod rather than 10.
If there would be disadvantage on the active check, subtract 5 from the passive. prof + mod
If there would be advantage on the active check, add 5 to the passive. 10 + prof + mod

If a PC should succeed 50% of the time on a non-modified DC 10 active check, a passive check shouldn't start at auto-success!

 

[iserith]

So a level one PC, without trying, sees everything that is "Hard" to see?

No, just the things that he or she is in the fictional position to see for the repetitive tasks on which he or she is focused. That comes with risks and trade-offs.