Gekkra Khania

Whenever you cast a creature spell, if it has mutate, put a mutation counter on this creature.
As long as this creature has one or more mutation counters on it, it gains the following abilities where X is equal to the number of mutation counters on it.
Whenever a creature enters the battlefield under an opponent's control, you may pay {1}{b}{b}. If you do, it enters with X -1/-1 counters on it.
Whenever a creature dies, you may pay {1}{u}{u}. If you do, scry X, then draw a card.
{1}{g}{g}, {t}: Create