Abnath, Plague Genesis

Eminence —At the beginning of combat on your
turn, put a +1/+1 counter on target creature you
control that doesn't already have one. It becomes
a Zombie in addition to its other types.
Whenever a creature you control with a +1/+1
counter on it attacks a player or planeswalker,
you may put a -1/-1 counter on target creature
controlled by defending player or remove a
loyalty counter from a planeswalker controlled
by defending player.