Evolutionary Nightmare

Adaptability (Whenever a creature enters the battlefield under an opponent's control, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)
During your upkeep, if Evolutionary Nightmare has 3 or more +1/+1 counters on it, sacrifice it. You lose life equal to it's power.

"Hey Tomigon... I think it's gonna blow... RUN!!"