Spawn of Grell

Whenever Spawn of Grell deals combat damage
to another creature, put a -1/-1 counter onto that creature and put a +1/+1 counter onto Spawn of
Grell.
{p/b}{p/g}: Spawn of Grell fights target creature an opponent controls.
Unknown to all on Elvendrain, Vorinclex infected
Grell and her brood with phyrexian oil in preparation
for Elsh Norn's invasion of the plane.