Originally Posted by Benmahalf X
Happened to me (PS3) when I was fighting some trolls and mammoths. Had to map to quite a few of their locations before I found him again, standing around as if nothing had happened.
But if you just need him for upping your destruction level, you could go to the Dark Brotherhood Sanctuary instead. If you have the prison rack you can use them to the same effect (but they need to be healed!)
Yeah I could always use that, and just use some sort of restoration spell or something to heal them.