Skeleton Crusader

Dethrone (Whenever this creature attacks the player with the most life or tied for most life, put a +1/+1 counter on it.)
Persist (When this creature dies, 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.)
"Did you see their banners? That kingdom fell a thousand years ago!" - Radolf, Field Marshal