"Someone doing magic to make them, most often, or a hostile god in the area, or a leakage of negative energy across the planes, or something like that."

"...Hostile god? Leakage of negative energy across the planes???"

"Neither of those is common at all. And I'm the wrong sort of cleric to deal with a hostile god, but an energy leakage isn't that hard to handle if you catch it early enough; I helped with one once." Yawn.

"I have never heard of either of these things. I mean, I've heard of entities that tried to become gods and failed and it went badly, but..."

"Well, it sounds like this is a different world, you might not have them here at all. Hostile gods are just - gods, of things that are bad for people, most of them don't have anything to do with undead but some do. Usually pretty weak ones, as gods go, not many people will follow one like that. And planar cosmology I probably shouldn't try to explain on two hours' sleep if you've never heard of it before."

"I...see. Yes, I can get you somewhere to sleep."

"Thank you. I should be okay to keep looking for a while, though, planar cosmology's just complicated."

"These are just low-level walking corpses, we can easily handle it." 

"All right." He takes one last look around and turns to head back toward Cloud Recesses. "I'm Raafi, by the way, and my god is Fharlanghn." He drops into a different accent to pronounce the names. "His title is Dweller on the Horizon, if you prefer."

"I have never heard of that deity but I suppose I wouldn't have."

"Doesn't surprise me, yes. You do have gods around here, though? What are they like?"

"Mostly once they get to the point of being gods they don't do that much on earth. Smaller local ones can be more helpful." 

"Huh. The gods I'm used to are mostly very interested in mortal affairs, and even the ones that aren't are important that way."

"Huh." 

He leads him to a sort of campus of long, pale, peaceful buildings.

Raafi follows agreeably enough, chatting to keep himself awake as they go.

"Should I look for someone in the morning, or anything?" he asks, when they get to the guest quarters. "And is it going to be an inconvenience to have me join you for meals? I can conjure food if it is, I just need to prepare the spell for it."

"Conjure food?"

"Mmhmm. Not quite as useful as it sounds, but maybe I'll prepare that one anyway, as a demonstration. Anyway, is there anything else I should know tonight?"

"...Uh, everyone rises at five."

"All right. I might be up a bit before that, but I can be careful not to disturb anyone. Thank you for your help."

"You're welcome." 

He sleeps, and wakes up comfortably before dawn to do his devotions, pacing quietly around the room.

They'll find him sitting outside the building the next morning, reading from a notebook and nibbling on dried fruit, with a walking stick he didn't have the night before propped against the wall beside him.

"So, you're our mysterious stranger." 

"That's me!" He tucks the notebook and pouch of fruit away and stands. "I assume someone wants my story."

"That would be lovely."

"There's not much to it, exactly. I seem to be from a different world - the young man who found me last night seemed very surprised at how my magic works - and I appeared in this one in my sleep last night, I have no idea why." He's awfully cheerful about it.