Gravelrath, Spine of Skuvern

Gravelrath, Spine of Skuvern enters the battlefield tapped unless you control two or more creatures with total power 6 or greater.
{1}, {t}: Add {r/g}{r/g}{r/g}. (You may spend {r/g} to pay for costs with {r} or {g} in them.)
{r/g}{r/g}, {t}: Exile target noncreature card from your graveyard. When you do, destroy target noncreature, nonland permanent an opponent controls.