Cal Darrow, Dread-Lord

As Cal Darrow enters the battlefield, put a phylactery counter on an artifact you
control.
Cal Darrow has indestructible as long as you
control an artifact with a phylactery counter on it.
At the beginning of your upkeep, create X
2/2 black Zombie creature tokens, where X is
half the number of Zombies you control,
rounded down.