Mephitic Monstrosity

Mephitic Monstrosity enters the battlefield with
five Demonic counters on it.
Whenever a creature dies, exile it instead, then
put a demonic counter of Mephitic Monstrosity.
Any opponent may pay {x}{x} to remove all
activated abilities from Mephitic Monstrosity
until the end of turn.
{4}: You may cast one card exiled by Mephitic
Monstrosity each turn without paying it's
mana cost.