Ashborn Ghoul

Devolve (Whenever a creature enters the battlefield under your control, if its power or toughness is greater than this creature's, put a -1/-1 counter on this creature.)
Persist (When this permanent is put into a graveyard from the battlefield, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)