The Mimeospawn

At the beginning of your upkeep, you may exile target creature card from your graveyard. If you do, put a +1/+1 counter on The Mimeospawn and it becomes a copy of that card until end of turn. Then you lose life equal to the number of cards exiled with it.
"What could a little ol' slime grow into, eh? It'll make the perfect pet!" -- Biomancer Zwanzic, Last Words