Recycling Den

{1}, {t}: Add {b} or {g} to your mana pool.
{b}{g}, {t}, Exile a creature card from your graveyard: Put a number of +1/+1 counters equal to that card's converted mana cost on target creature.
The Spikes of Dominaria don't even hesitate to feast from their dead in order to survive. You can call that evolutionary instinct, I guess ...