Rustfire Avenger

Unleash, Modular 0, Bloodthirst 1 (You may have this enter the battlefield with a +1/+1 counter on it. If an opponent was dealt damage this turn, it enters the battlefield with another +1/+1 counter. It can't block as long as there's a +1/+1 counter on it. When it dies, you may put its +1/+1 counters on target artifact creature.)
Mere death hardly ends a feud.