Open the Necropolis

Create X 2/2 black Zombie creature tokens, where X is the number of creatures in target player's graveyard. Open the Necropolis deals
X damage to you. Experiment.
{2}{b}: Return Open the Necropolis from your graveyard to your hand.

Grendhelt sliced across his wrist, and at the taste of his blood the corpses awoke once more.