Here's a discussion I don't have the slightest clue on what the correct answer is.
Blindsense specifically says that an individual does not need to make a perception check to identify a target in it's range.
The issue is whether or not the brain of a given PC would wake up to something triggering the blindsense. Consider we aren't conscious so we can't decipher whether or not the sense is important, it's all down to our autonomic response, akin to hearing I guess, you don't decide in your sleep whether or not the sound is important, you wake up then make sense of it.
How would you rule this? What even is blindsense? The official rules seem very vague in this sense. My current interpretation is that you'd either know straight away and wake up, or your brain wouldn't be wired to wake up to things detected in blindsense thus not relevant when something is sneaking around you campsite at night.
I agree, Blindsense is pretty vague, and the specifics are left up to how the creature's blindsense manifests. As a general rule, I'd say blindsense doesn't do anything while you're sleeping. It's an ability specifically for pinpointing creatures you can't see, so I assume it simply replaces any attempt to pinpoint a target in combat with an automatic success.
As a compromise, they could have the +8 to perception checks given to those with tremorsense and scent, but would still suffer the -10 from sleeping.
Blindsense is meant to be a lot weaker then blindsight- for instance it won't help against illusions unless the creature closes it's eyes.
I might, OTOH, give a creature with Tremorsense some chance to be disturbed by a big heavy platemail clad creature sneaking up on it. Or a creature with scent to be alerted by a torch carrying dude.
I'd give some sort of check to "notice" and wake up but it would more be about the creature sleeping. I sure can hear all kinds of things at night while I'm sleeping, I certainly don't wake up for all of them or else I'd never sleep.
Not all stimuli will or should wake up.
For an easy ruling, I'd probably just say blindsense doesn't work while you're sleeping, and instead you're relying on sound (unless your blindsense calls out it's sound based, though very few enhanced senses specify how they work). Thus to notice the creature sneaking up on you in your sleep you would make a perception check (at -10 for sleeping) against the creatures stealth score. Just like anyone else.
Having a high perception being representative of training yourself to notice details that might be important, even when sleeping.
Make a perception check away the usual -10, but using blind sense.
Make a perception check away the usual -10, but using blind sense.
I had the same immediate thought.
If a creature is asleep, they add +10 to an opposed Stealth vs. Perc check and add +1/10DC for every 1ft they are away from the Stealthing creature. (per Perc DC Mod rules). If they fail, they notice nothing, if they pass, they notice that there is a creature present and can become roused if they wish. Once awake, Blindsense would allow them to sense the creature without making an additional Perc check (such as if the creature making the Stealth check is invisible).
The original Stealth vs. Perc check would be performed without the +20/+40 from Invis, but only if they're within range of Blindsense.