Primal Engagements

At the beginning of your end step, sacrifice a
creature and put a +1/+1 counter on target
creature you control. If you can't, sacrifice
Primal Engagements and return a target
creature from your graveyard to your hand.
Whenever a creature you control gains one more
+1/+1 counters on it. That creature may fight
another target creature you don't control.