Ervus

Flying, trample, wither
Whenever a creature with a -1/-1 counter on it
dies, create a 1/1 black, red, and green Ooze
creature token.
{r}, put a -1/-1 counter on Ervus: Ervus deals
1 damage to any target.
{b}{b}{g}{g}, sacrifice 5 creatures: Return Ervus
from your graveyard to the battlefield.