Wraiths

Wraith are the souls of dead clerics, returned to the world of the living through Mondain's spells. They act as his servants, attempting to turn others to Evil in his name -- that is, inducting them into their ranks through undeath. Wraiths are frighteningly resistant.

Wraiths were found only in the darkest dungeons of old Sosaria. When Mondain was defeated, these unrestful spirits were released from his control, apparently returning to their graves.