@Hael Yes. Right now about 1/100 return due to a curse Vestec cast to annoy Reathos even more. The undead right now act pretty much like they did alive. Well, maybe with some emotional problems due to well dying. I believe
@Rtron did mention that angel would turn intolike vampire lords (leathery wings I'm guessing). How it functions is simple: the souls don't leave the bodies. Thus the dead rise again.
However, I am planning on making Reathos cast an extra curse of the undead, making them mad with a hunger to kill (in case of humans, Hain and most Rovaick) or a thirst for blood or human meat (vampire and the undead Azibos).
That aside, soon Reathos will also raise his own undead to help out the Pronobii currently fighting a losing battle against Vestec's horde. These will be simple animated bodies, without a soul.