Caduceus Clay, Grave Cleric

Undegrowth-Caduceus Clay enters the battlefield with as many green/black 1/1 insect creature tokens as there are creatures in your opponents' graveyards.
{1}{b}-Exile a creature card from a graveyard. Create a 1/1 green/black insect creature token.
{1}{b/g}{b/g}-Target creature has -1/-1 until end of turn.