[Kristoffer O]

Originally posted by calmon:
But the mummy is undead too. Isn't it better to let it die definitely after the second (undead-state) death?

In moment you can rebirth both Vampire Queens (wished one) and mummies. Didn't test the other undeads/lifeless.

The mummy is almost an immortal. You can rebirth him, but it will cost you a bit. This is intended. The restriction on other undead was a later fix. Removing abdominal content, putting it in jars and wrapping the body in linen felt strange when applied to wraiths and several other undead.