Gellerpox Infected

Double Strike

Whenever an opponent casts a non black or
green creature spell, you may put a +1/+1 counter on a creature you control.

Creatures in your graveyard have Eternalize {4}{b}, (Exile this card from your graveyard: Create a token that’s a copy of this card, except it’s black, it’s 4/4, it has no mana cost, and it’s a Zombie in addition to its other types. Activate this ability only any time you could cast a sorcery.)