D&D 5E Understanding Passive Checks

[Hriston]

The passive rules as written don't make sense. They represent the average score of a task done over and over again, which means that the PC is rolling 1s, 2s, 19s, 20s, etc. as he walks and the passive score is just the average of all the rolls the PC is constantly making. However, it makes no sense for the PC to always be rolling the average at every moment that's important and needs to check the passive skill.

For that reason, I don't use passive skills.

It's your prerogative as DM to ask for an active roll or to use the character's passive score to resolve a check, but I find the idea that "checks" are constantly being made in the fiction of which the passive score is an average to be an odd one. The way I read the rule is simply that the DM can substitute 10 in place of a rolled result when deemed appropriate.

 

[billd91]

It's your prerogative as DM to ask for an active roll or to use the character's passive score to resolve a check, but I find the idea that "checks" are constantly being made in the fiction of which the passive score is an average to be an odd one. The way I read the rule is simply that the DM can substitute 10 in place of a rolled result when deemed appropriate.

I don't know why that would be odd. Perception is one of those odd skills that is, literally, always going on. While someone may be concentrating on a task and that be reflected as a discrete application of a skill, they're always engaging some degree of perception of their environment. As a result, there's always a chance of noticing things whether a draft from a hidden passage, a sneaky assailant creeping up, or an ambush set in place. The real question is how to give the DM a tool to handle that without disrupting the flow of the game by asking for checks that may be metagamed. And the average score, Taking 10 in previous editions, is a simple and effective way to handle it.
I just don't see why it's an odd idea.

 

[Hriston]

I don't know why that would be odd. Perception is one of those odd skills that is, literally, always going on. While someone may be concentrating on a task and that be reflected as a discrete application of a skill, they're always engaging some degree of perception of their environment. As a result, there's always a chance of noticing things whether a draft from a hidden passage, a sneaky assailant creeping up, or an ambush set in place. The real question is how to give the DM a tool to handle that without disrupting the flow of the game by asking for checks that may be metagamed. And the average score, Taking 10 in previous editions, is a simple and effective way to handle it.
I just don't see why it's an odd idea.

I have a feeling you might not have understood what I was talking about. I was talking about @Maxperson's idea that a PC is constantly rolling checks as they walk around so that the passive score is meant to be an average of those checks. That's what I find odd.

You're constantly perceiving something, but you aren't constantly making checks. You only make a check when there's a chance to notice the hidden passage, sneaky assailant, or ambush, which is when the passive score is referenced if the DM decides to resolve the check passively.

 

[Maxperson]

I have a feeling you might not have understood what I was talking about. I was talking about @Maxperson's idea that a PC is constantly rolling checks as they walk around so that the passive score is meant to be an average of those checks. That's what I find odd.

That's what RAW describes, though.

You're constantly perceiving something, but you aren't constantly making checks. You only make a check when there's a chance to notice the hidden passage, sneaky assailant, or ambush, which is when the passive score is referenced if the DM decides to resolve the check passively.

Yes, but you aren't always perceiving at a constant level. It fluctuates pretty wildly. I've been in a room and spotted a small bug sitting on the far wall without trying, and the other night I was helping a friend find the dog cone to put on his dog and missed it sitting on the floor to my right. Adventurers wouldn't have a constant number for their passive checks, either.

 

[Jfdlsjfd]

The bug rolled very low on his Hide check and was unable to beat your passive perception. Looking for the dog cone certainly involved some kind of stress -- you were both searching, presumably with some kind of time pressure or desire to be helpful by finding it -- so your rolled Perception and did low. I find your example actually reinforcing the RAW.

It wouldn't make sense to use the average since a good roll is enough, so with enough time one would be bound to succeed at detecting anything by virtue of rolling 20. I think it's meant to represent the "common performance" of a skill, without pressure that would enable low result or adrenaline that would allow exceptional performance.

I am strangely bugged more by the d20 variability to reflect regular performance at a task... (if you visit the dentist, you expect him to succeed to treat a tooth, despite probably having an un-heroic +3 or +4 modifier)

 

[Hriston]

That's what RAW describes, though.

"Such a check can represent the average result for a task done repeatedly"​

​

Notice that it says "a task done repeatedly" not a check done repeatedly. Also, it uses the word can to denote this is just one of the uses for a passive check.

Yes, but you aren't always perceiving at a constant level. It fluctuates pretty wildly. I've been in a room and spotted a small bug sitting on the far wall without trying, and the other night I was helping a friend find the dog cone to put on his dog and missed it sitting on the floor to my right. Adventurers wouldn't have a constant number for their passive checks, either.

That's a good reason not to use passive checks. It does result in a given character always having the same check result.

 

[Maxperson]

"Such a check can represent the average result for a task done repeatedly"​

​

Notice that it says "a task done repeatedly" not a check done repeatedly. Also, it uses the word can to denote this is just one of the uses for a passive check.

That's a distinction without a difference. They are doing the task(perceiving) repeatedly and then taking the average result of all those tasks. If they weren't checks, there would be no average result.

 

[Charlaquin]

That's a distinction without a difference. They are doing the task(perceiving) repeatedly and then taking the average result of all those tasks. If they weren't checks, there would be no average result.

No, they are doing the task repeatedly and then making one check, called a passive check, which uses the average result of a roll to perform that task (rounded down, as usual in D&D) to determine the net result of the character’s efforts over a period of time.

 

[jgsugden]

If it doesn't make sense to you, think of it another way.

When you're using passive perception you're getting the benefit of 'unconscious' skill use. You're not trying to be perceptive. You just might notice something.

Why will your '10' result always be higher than your lowest rolls? Because you get the time to attempt it several times. It makes sense that you're not going to always get low rolls, so it is appropriate to have the roll be effectively at least a 10. And, if it isn't appropriate, a -5 penalty applies if the DM decides there should be disadvantage.

Why will your '10' always be lower than your highest rolls? Because you're not giving it your best effort, either.

I use a lot of passive checks. Essentially, all wisdom, intelligence and charisma rolls that are not under time pressure treat the passive score as a floor for the ability check, and are applied even when the PC doesn't say they're trying to do something. I do not use them for dexterity and strength 'rolls' often, as there is usually a time pressure and a single chance to get it right. However, I do use it for athletic things like a longer race, or a swim through difficult waters that is more than a couple moves wide.

Does this step on reliable talent? No. generally it does not. Most of the rolls where it matters is where there is a time pressure - and only the reliable talent gets the benefit of the passive floor for those rolls.

 

[FrogReaver]

For the most part I hate passive checks in 5e.

Sneaking up on a single guard under 'normal' circumstances makes sense to use passive perception as the DC for your sneak.

Sneaking up on an encampment of guards, it makes no sense to use passive perception of the guards as the DC for your sneak (or the active for that matter). The particular encampment itself is what needs the DC in this situation and the advice to rely on passive perception (or active perception) makes for a terrible way to set the DC.