Forsaken Alchemist

When Forsaken Alchemist enters the battlefield,
you may create a 2/2 black Zombie creature
token.
{b}{t}: Sacrifice a Zombie. Plague 1 (Put a plague
counter on target creature. At the creature's
controller's upkeep, add 1 plague counter on that
creature. If plague counters are equal to or
greater than that creature's toughness, sacrifice it.
Its controller chooses another one of their
creatures. That creature gets 1 plague counter.)