D&D 5E I need some "Watchdog" Monsters

[Stalker0]

So for an upcoming game, I need some monsters that are good watchdogs, aka would have a high passive perception score.


The best one I found so far was the barbed devil with an 18, or the wolf also with an 18 (if you assume the keen sense adds +5 to its passive, which I do).


Is there anything better out there?

 

[Tales and Chronicles]

There's the Mindwitness,
Nothics have true-sight
Dire trolls have a PP of 15 + Keen senses (sight and smell)
Worgs are PP 14 + keen senses (hear and smell)
Gazers and Gaunt arent all that bad either
Hell hounds and hook horror are also good for the job.

 

[Mort]

What about an Intellect Devourer?

doesn't have a high passive perception, but automatically detects, and knows the exact location of, any sentient creature (as in INT 3 OR higher) within 300 feet.

Plus, for CR 2, they are nasty little buggers.

 

[MarkB]

D&D Beyond has some nice options under advanced filters. A few highlights from searching for tremorsense, truesight and/or trained Perception:

Bulette - Tremorsense 60 feet, passive perception 16
Canoloth (fiend, MToF) - Truesight 120 feet, passive perception 19, cannot be surprised
Gynoshynx - Truesight 120 feet, passive perception 18
Korred - Tremorsense 120 feet
Orthon (fiend, MtoF) - only 30 foot Truesight, but passive perception 20

EDIT: Just noticed this under the Canoloth's description, which would make them ideal for your uses:

"Canoloths prefer to enter into contracts to guard valuable treasures and important locations. They always do exactly as asked — never any more, never any less."

 

[Levistus's_Leviathan]

Spectators.

Need I say more?

(If you want something else, the others have suggested good options. I particularly like sphinxes, canoloths, intellect devourers, and nothics, as well.)

 

[Arvok]

Faithful Hound spell? Maybe even home-brew a version or magic item that lasts more than 8 hours.

 

[Mannahnin]

How about Death Dogs? Advantage on Wisdom (Perception) and Percept +5.

 

[Flamestrike]

So for an upcoming game, I need some monsters that are good watchdogs, aka would have a high passive perception score.


The best one I found so far was the barbed devil with an 18, or the wolf also with an 18 (if you assume the keen sense adds +5 to its passive, which I do).


Is there anything better out there?

But... you're the DM.

Pick any monster. Give it profiency in perception. Expertise even. It's been specially bred (or recieved the appropriate training).

 

[CleverNickName]

I'd probably go with an actual watchdog. I'd take a bog-standard mastiff from the Monster Manual, give it a special ability or the Alert feat (or the Observant feat, or both, similar to what @Flamestrike suggested.) In the description, I'd add a blurb like this:

Watchdog. This hound has received special training from the Captain of the Guard, and is more alert and perceptive. As a result, this watchdog cannot be surprised while she is conscious. She has a Passive Perception of 18, makes Initiative checks at +5, and has Advantage on all Intelligence (Investigation) and Wisdom (Perception) checks that rely on hearing or smell. She is also a very good girl.

And for those who like the simple approach, there's always shriekers.

 

[dave2008]

What level / CR range? Dragons have a high passive perception. A young red dragon (CR 10) has a passive perception of 18 and it goes up from there.

Are you looking for WotC monsters or would 3PP or homebrew work? Here are some of mine with high passive perception:

• Aarakocra Guard (standard, CR 1)
• Couatl, Guardian (standard. CR 5)
• Timber Wolf (standard CR 1/2)
• Yuan-ti Abomination Guard (standard, CR 11)
• Unicorn Elder (Legendary, CR 7)