Demilich

A demilich.

The demilich is the "evolved" form of the lich. Demiliches have largely abandoned their physical bodies, undergoing a process of absorbing souls to empower their ascension. Their jewel-toothed skulls are all that remain in the physical world (save dust that was once their bones), while their undead spirits roam other realms. The presence of intruders or attacks on their physical forms can awaken demiliches, who are incredibly deadly foes in battle.

Comments

They are apparently called "demi"-liches because of the decay of their physical form.