Passive ability checks

[Sileas]

Complete noob here.

My sister and I are in the beginning stages of fooling around with Dunjuns n draguns. I'm going to be the DM and also going to be playing a character----yaaas, I realize that's gonna make things complex, but it's just the two of us. The world can't blow up from this.

There is one subject...well, actually a couple, but we'll just start with one. Passive ability checks. I have the 5th edition player's manual (and a monster manual and a DM manual) and I cannot figure out the passive ability check. Page 175, first column, about halfway down. Makes, like, no sense to me. I understand what it is in principle and how it's used--I just don't understand how it's calculated. Can anyone explain in very small words and short sentences how to do these?

thanks much for the brains.

[PhoenixPhyre]

Complete noob here.

My sister and I are in the beginning stages of fooling around with Dunjuns n draguns. I'm going to be the DM and also going to be playing a character----yaaas, I realize that's gonna make things complex, but it's just the two of us. The world can't blow up from this.

There is one subject...well, actually a couple, but we'll just start with one. Passive ability checks. I have the 5th edition player's manual (and a monster manual and a DM manual) and I cannot figure out the passive ability check. Page 175, first column, about halfway down. Makes, like, no sense to me. I understand what it is in principle and how it's used--I just don't understand how it's calculated. Can anyone explain in very small words and short sentences how to do these?

thanks much for the brains.

Passive checks (which are most common for passive Wisdom (Perception) checks, often to find hidden ambushers) are calculated as follows:

Check result = 10 + ability score + proficiency (if proficient).

So a level 1 cleric with a 16 (+3) wisdom and proficiency in perception would have a passive Wisdom (Perception) score of 10 + 3 (Wisdom) + 2 (proficiency) = 15. A level 20 fighter with +2 wisdom and no proficiency in perception would have a passive Wisdom (Perception) score of 10 + 2 (wisdom) = 12.

The 10 comes from assuming the d20 rolls its average (10.5) and rounding down.

Edit: and these check results are compared either to a fixed DC (for a hidden object or the like), or, more commonly, to an actively-rolled check such as a Dexterity (Stealth) check made by a creature trying to hide from the observer.

[Sileas]

Thank you for the head-spinningly fast response.

That seems, like, well, makes more sense than the book. Is there a typo in the book?

"For example, if a 1st level character has a wisdom of 15 and proficiency in perception, he or she has a passive wisdom (perception) score of 14."

Looking at that, I think alright, 15, and the level-related modifier is +2, so I would think it should be 12, but....14....?

[Lunali]

Thank you for the head-spinningly fast response.

That seems, like, well, makes more sense than the book. Is there a typo in the book?

"For example, if a 1st level character has a wisdom of 15 and proficiency in perception, he or she has a passive wisdom (perception) score of 14."

Looking at that, I think alright, 15, and the level-related modifier is +2, so I would think it should be 12, but....14....?

You're missing the "and proficiency in perception," giving another +2 at first level.

[Sileas]

Ahhh yes. Just found it in the book. Ok, starting to wrap my head around this. Thanks much, all!

[Louro]

You have two options here.

1. Classic
Make players roll perception checks (or roll them yourself).

2. Use passive perception.
This avoids rolls, it's faster and players don't know something is going on.

If you choose to roll perception behind the screen (so players don't know if they succeeded or not) you can randomly roll from time to time to decide them.

Passive perception kicks in when a character is actively searching or alert. Someone who is not paying attention won't have his passive perception active (or just disadvantage, which is a -5).

[Lunali]

If you choose to roll perception behind the screen (so players don't know if they succeeded or not) you can randomly roll from time to time to decide them.

Passive perception kicks in when a character is actively searching or alert. Someone who is not paying attention won't have his passive perception active (or just disadvantage, which is a -5).

You generally want to roll regardless, the difference is whether you're rolling perception or stealth/deception/whatever.

[Greywander]

Complete noob here.

My sister and I are in the beginning stages of fooling around with Dunjuns n draguns. I'm going to be the DM and also going to be playing a character----yaaas, I realize that's gonna make things complex, but it's just the two of us. The world can't blow up from this.
My sister and I are also doing this. How it's worked out so far is that one of us will generally act as the primary DM for one "arc", and then switch off after each arc. The primary DM would generally be in control of deciding where the story goes, but you should also work together and maybe you'll end up with something more interesting than just one of you could come up with. Do be careful not to let the power of being DM go to your head and allow you to treat your own character favorably while mistreating your sister's character. Remember, even as a DM, you're still on the same team with the players. Your goal in playing as the monsters is to provide an interesting challenge or story.

On that note, I've also found it helpful to allow your co-DM to act as the DM (even when you are the primary DM) when your character is trying to get something from an NPC. For example, if I am the primary DM, but my character is interrogating an NPC, my sister will take control of the NPC and perform rolls for them. She may need to consult with me to find out how this fits into the current story arc and what I should or shouldn't be getting out of them if I roll well, but she's also free to just make something up if it seems like it would fit. This has lead to interesting developments that I didn't expect.

In a situation like this, it's also much more important to separate in-character and out-of-character knowledge. Just because you, the player, "know" something, especially if you are acting as DM, doesn't mean that you, the character, "knows" that same thing. As a DM, you might "know" that a character is a spy, but if you fail your Insight check then you might not "know" in-character. In a case like this, you would want to pretend like you don't know they're a spy, while also scheming up interesting things you can do as a DM since you do know that character is a spy. One thing to remember is that failure is often much more interesting than success! Don't be afraid to plot your own downfall if your character is too stupid to realize something important. It will make for a better story when you persevere and overcome in the end!

One last piece of advice on this subject: a virtual DM can be invaluable. If you have a disagreement with your sister, or if you're just not sure what to do next, you can ask the virtual DM and have it resolve it for you. Now, a virtual DM works best with yes/no questions, although some are capable of, say, generating a random NPC or location, though even then they usually require a human to make sense of the given description and incorporate it into the current story. The one we've been using is RPG Solo (https://www.rpgsolo.com/), which is free to use. What you'll probably use the most from RPG Solo is the "Get Answer" feature found in the bottom left of the screen. The buttons range from "Almost Impossible" (AI) to "Sure Thing" (ST) with 50/50 being in the middle. The answers usually take the form of "Yes, and..." "Yes, but..." "No, but..." et cetera. For example, you might peek into a room and ask, "Are there any guards?" You might hit the SU (Somewhat Unlikely) button and get "No, but..." This could mean a couple of things, but you decide that it means that there aren't any guards, but there is a maid in the room cleaning. Or maybe you get "Yes, and..." which might mean that not only are there guards in the room, but General Tiberius himself and his entourage of elite bodyguards are in the room.


There is one subject...well, actually a couple, but we'll just start with one. Passive ability checks. I have the 5th edition player's manual (and a monster manual and a DM manual) and I cannot figure out the passive ability check. Page 175, first column, about halfway down. Makes, like, no sense to me. I understand what it is in principle and how it's used--I just don't understand how it's calculated. Can anyone explain in very small words and short sentences how to do these?

thanks much for the brains.
This one's already been covered, but passive skills are 10 + ability score modifier + proficiency bonus (if proficient). Lunali is right in that generally passive skills allow the DM to make the rolls instead of the player. This helps speed the game up (asking a player to roll then waiting for them to roll takes longer than just rolling yourself), and prevents the players from getting paranoid and getting sidetracked ("Roll Perception. Okay, you don't see any ninjas sneaking up on you with weapons drawn."). Instead of making the players roll Perception, you just roll Stealth for the monsters and weigh it against the players passive Perception skills. You can also use passive Perception to indicate how much info to give out when they first enter a room, instead of requiring Perception checks to see or notice things in plain sight. You can do the same with passive Knowledge checks, just telling them things they would know if their knowledge skills are high enough. Likewise for Insight checks when an NPC is trying to manipulate them.

In a nutshell: when they first enter the room, use passive Perception to decide how much they see/notice. If they decide to search the room, that's when they would roll a Perception check, and since they're actively searching, even a poor roll (less than their passive) might uncover something they didn't notice before. Or, if an NPC is lying, use passive Insight. If the players suspect the NPC is lying, they might roll an active Insight check to specifically watch for tells (of course, the NPC might notice this extra scrutiny, too, so they might not always want to do this).