[quote=solamelike]
You should talk to lore master if his character told you, if not we can say you have your suspicions. Raising people from the dead is very rare so your character would probably just think he was some kind of ugly humanoid creature that smelt bad.
[/quote]

Well considering he has knowledge at 5 is it something he would perhaps know? Or will it require a roll if he manages to pick up on something that might suggest he is an undead?