D&D 5E Stealth and sleeping creatures

[Sword of Spirit]

I'm trying to figure out how to handle the ability of a sleeping dragon to notice creatures around it. The dragon has blindsight, which complicates the matter a bit, but I realized I'm not even sure how I want to handle stealth around sleeping creatures in general.

Xanathar's Guide to Everything has some rules about waking up creatures, but they are less useful than one might hope. They focus on sound volume of voices, but don't mention anything about intentional attempts at stealth. You might be trying to keep your voice to a whisper or less, but you can still step on a branch or have creaky armor--these rules don't integrate that basic element of stealth.

The call I most recently made was to give a -10 to Passive Wisdom (Perception) for a sleeping creature to notice characters attempting to use Stealth, but I actually thought that was from XGtE (it wasn't, and I'm guessing I'm remembering a rule from 3.x, which isn't a mistake a usually make, but that seems like the most likely outcome). The number is awfully big for 5e (5e would usually just say you can't do something rather than give it that sort of penalty), and I prefer not to break with 5e standards when possible. That means it should probably be handled in terms of absolute yes/possible yes/no, and Advantage/Disadvantage as modifiers within "possible yes" category.

So how would you handle sleeping creatures noticing stealthy characters, taking into account 5e standard operations and the specific details about waking in in XGtE?

 

[Seramus]

Blinded creatures automatically fail perception checks based on sight. I allow perception at disadvantage (or passive -5) for hearing or smell.

 

[Hriston]

I give sleeping creatures the Unconscious condition, making them completely unaware of their surroundings. The only way they can notice anything is if they wake up, which they will do if there is a loud noise or something I consider to be the equivalent, like being attacked. Dragons are an exception. Sometimes they wake up for no reason at all.

 

[iserith]

Disadvantage on passive Perception seems like the way to go here. If the creature has blindsight (as with a dragon) or perhaps a relevant Keen Sense trait, then give them advantage which offsets disadvantage.

 

[Oofta]

Depends on how you want to run it. A dragon in my campaign has blindsight because he uses senses other than sight and sound. Smell, sensing vibrations, even just noticing changes in air current.

But the dragon is asleep so I'd give them disadvantage on their perception.

Of course I'd also have wards and traps so you couldn't sneak in but that's another story.

 

[DND_Reborn]

We do sleeping is -5 on passive perception. If the stealth is above the modified passive perception, the PC is quiet enough the target doesn't hear them to even consider waking up.

Now, we handle passive perception differently that RAW, so I am sure if this will help you or not. We rule if your passive score beats their stealth, you get to roll your perception against it. It isn't automatic!

 

[pnewman]

There are no rules that say that blindsight has any penalty just because you are asleep.

I would just give them a -5 to their Passive Perception, because being asleep should put you at a disadvantage.

 

[pnewman]

I give sleeping creatures the Unconscious condition, making them completely unaware of their surroundings. The only way they can notice anything is if they wake up, which they will do if there is a loud noise or something I consider to be the equivalent, like being attacked. Dragons are an exception. Sometimes they wake up for no reason at all.

The test of the "Sleep" spell supports this interpretation, because it causes unconsciousness and it refers to those affected as "sleepers".

However, it is just not 100% true that a sleeping person is totally unaware of their surroundings, or how would alarm clocks work?

Maybe they're unaware of their visual surroundings but, since they are not Deafened, they can still hear?

 

[Seramus]

However, it is just not 100% true that a sleeping person is totally unaware of their surroundings, or how would alarm clocks work?

My alarm clock usually beats my passive perception. When it doesn't I sleep right through it!

 

[Shiroiken]

I think a -5 to passive perception and/or advantage on the stealth check would be sufficient. In general an unconscious creature is unaware of their surroundings, but someone being particularly loud (someone clanking around in heavy armor for example) might wake them. Interestingly, I'd not have that affect PCs if anyone ever takes a watch while wearing heavy armor, since they'd be used to the noise. As for the sleep spell, that's a magical effect that specifically ignores loud noises.

As for dragons, a sleeping dragon was always a method to allow PCs to face a dragon more powerful than they might otherwise face, giving them a round to start things off. However, many a cruel DM (myself included) have had dragons fake being asleep to lure the party into a trap.