I think it would be cool if the current undead that don't have any evolution could combine into a super creature like or . I could have like 5 arms and 2 heads, and an arm where a leg would be. Like a conglomerate monster created by a psycho craftsman. Also could be used to introduce craftsman to the Nehant. Or if that is wildly opposed I suppose you could say an evil magician magicked the creature together.