Creytoria, Apex Dreadmaw

Creytoria, Apex Dreadmaw can't be countered.
Menace, trample
Whenever a permanent an opponent controls
becomes a creature, or a creature enters the battlefield under an opponent's control,
Creytoria, Apex Dreadmaw fights it.
Damage is not removed from Creytoria, Apex Dreadmaw during the cleanup step.