D&D 5E Trained Watch Dog

[TaranTheWanderer]

A player has a Mastiff and has it trained as a watch dog (not for riding).
The write-up says its passive perception is 13

But the write up also says it gets advantage on perception checks:
Keen Hearing and Smell: The mastiff has advantage on Wisdom(Perception) checks that rely on hearing or smell.

Shouldn't the Passive Perception be 18?

Also, how many DMs out there (the ones that use passive perception), allow Player's familiars and mounts to make perception checks, and do you give them the +5 bonus?

 

[Oofta]

Perception can be sight-only checks in some cases. If you think sight or sound could clue in the dog feel free to give a +5.

 

[jaelis]

Passive perception would be 18 for checks relying on hearing or smell, but only 13 for checks relying on vision. So it depends what the hound is trying to observe.

I let pets use their special senses where relevant, yes.

 

[Shiroiken]

Also, how many DMs out there (the ones that use passive perception), allow Player's familiars and mounts to make perception checks, and do you give them the +5 bonus?

Something like the mastiff I'd allow its passive perception, because that's largely the point of the animal, but I normally ignore mounts and standard familiars. Special animals, such as a warlock's chain pact familiar or a paladin's summoned mount, I'd take into consideration.

 

[Inanity]

A player has a Mastiff and has it trained as a watch dog (not for riding).
The write-up says its passive perception is 13

But the write up also says it gets advantage on perception checks:
Keen Hearing and Smell: The mastiff has advantage on Wisdom(Perception) checks that rely on hearing or smell.

Shouldn't the Passive Perception be 18?

Also, how many DMs out there (the ones that use passive perception), allow Player's familiars and mounts to make perception checks, and do you give them the +5 bonus?

Dont think there is any rule that say advantage gives you +5 to the relevant role (I am aware, however, that it is apparently demonstrable that rolling 2d20, taking the higher result averages out to a value around 5 higher than merely rolling 1d20; but I dont think it is a rule or a variant rule, maybe a variant rule).

Also, passive perfeception is you and your (untrained) Bassett hound happily, if not aloofly, walking down the street... Compare to the hunting dogs sniffing out that duck in the pond; or the bloodhound tracking the fugitive..

This being said I would allow the player to teach their dog to actively search/etc. (i.e. it wouldnt be using its passive perception.. if you want a night time sentinel but dont want to scratch your head wondering how many checks to make (passive perc. solves this problem) maybe this is just a case where the DM may have to make the role in secrect (make one or two roles to simulate the animal actively perceiving and dont use passive; I would say the dog gets to role twice if woken up etc.

ANd I would also just give a player the +5.

 

[jaelis]

Dont think there is any rule that say advantage gives you +5 to the relevant role

...PHB pg 175

Passive Checks
If the character has advantage on the check, add 5. For disadvantage, subtract 5. The game refers to a passive check total as a score.

 

[Ovinomancer]

Dont think there is any rule that say advantage gives you +5 to the relevant role

Check again. Advantage on a passive check gives you a flat +5; disadvantage -5. Again, only to passive checks.

Here’s how to determine a character’s total for a passive check:
10 + all modifiers that normally apply to the check

If the character has advantage on the check, add 5. For disadvantage, subtract 5. The game refers to a passive check total as a score.

(I am aware, however, that it is apparently demonstrable that rolling 2d20, taking the higher result averages out to a value around 5 higher than merely rolling 1d20; but I dont think it is a rule or a variant rule, maybe a variant rule).

Not quite. If you're looking at it as a success increase, then the maximum delta is when you need a 10-11. This increases or decreases your odds of success by 25%, respective to ad/disad. Often, this get's shorthanded to +5, but this is, strictly speaking, incorrect. Useful, though, and why oassive checks, which are based on rolling a 10, use the +/- 5.

The further towards to top and bottom tge DC, though, the less delta ad/disad has, although the relative change is. Even if you shorthand to +/-, which is even more incorrect at the extremes, it diesn't average to +5.

Also, passive perfeception is you and your (untrained) Bassett hound happily, if not aloofly, walking down the street... Compare to the hunting dogs sniffing out that duck in the pond; or the bloodhound tracking the fugitive..

No, passive checks aren't distracted -- that's what disadvantage represents. Passive checks are repeated or sustained efforts. It's a tool of convenience so you don't have to roll hundreds of checks when looking out for traps going down a long dungeon corridor, not representative of a neutral state. If you're not doing the thing at all, you don't get a passive check for it.

From the basic rules:

A passive check is a Special kind of ability check that doesn’t involve any die rolls. Such a check can represent the average result for a task done repeatedly, such as searching for Secret doors over and over again, or can be used when the GM wants to secretly determine whether the characters succeed at something without rolling dice, such as noticing a hidden monster.

 

[Inanity]

No, passive checks aren't distracted -- that's what disadvantage represents. Passive checks are repeated or sustained efforts. It's a tool of convenience so you don't have to roll hundreds of checks when looking out for traps going down a long dungeon corridor, not representative of a neutral state. If you're not doing the thing at all, you don't get a passive check for it.

From the basic rules:

Thanks for the above comments! I would still say that a dog sniffing out a fugitive is an active check (there are active checks afterall, they happen sometime and that would be a good candidate; which I am aware that you didnt actually say the hunting dogs were passively perceiving; you were more concered with my other case, the distracted Basset hound)...
which, as the rules obviously indicate, and which i was ignorant, the dog has 18 passive perc (whether a vigilant guard dog is actively perceiving is another story though)... ...

 

[aco175]

Just remember when the PCs try to sneak up on the goblins that their wolves get it as well.

I get that the PCs want a watchdog and it would come in handy in lots of places. But, like a lot of things in a game like this, the rules do not always make complete sense. Good thing dogs die quickly in a fireball, or poisoned meat, or targeted by kobolds, or...

 

[Ovinomancer]

Thanks for the above comments! I would still say that a dog sniffing out a fugitive is an active check (there are active checks afterall, they happen sometime and that would be a good candidate; which I am aware that you didnt actually say the hunting dogs were passively perceiving; you were more concered with my other case, the distracted Basset hound)...
which, as the rules obviously indicate, and which i was ignorant, the dog has 18 passive perc (whether a vigilant guard dog is actively perceiving is another story though)... ...

So, the real difference between an active check and a passive one is how you want to approach it as a GM. You could ignore passive checks altogether and ask for rolls whenever they're needed, or roll them in secret. Not sure that's the best approach, but you can do it. Passive checks come in handy for repeated tasks, like being on watch, or looking for traps as you move through the dungeon. If you did active checks for these, there'd be a lot of them, or you'd clearly be rolling for important things, or you're now doing dummy rolls to hide the real ones, etc. Passive checks are good for these things.

The thing to realize is that there's nothing passive about Passive checks -- the character still has to be doing the action, just over a length of time or repeatedly. A dog on watch uses the Passive check not as a default, but because it's the averaged out value of lots of repeated checks. There's no such thing, really, as an active check, because checks are just checks -- there's no opposite or conflicting states between a check and a passive check. Passive checks are just averaged checks over time.

Dogs make excellent guards because they have scent. Scent is one of those things that is hard to hide. I generally rule that unless the character is taking specific actions to avoid being scented (staying downwind, using some form of scent masking, etc.) that they have disadvantage on Stealth checks with regards to scent. This won't stop a high level rogue at all, but it does mean sneaking the party past some guard dogs suddenly because a challenge moreso than "I roll stealth."