Predatory Abomination

Mutate {p/g}{p/g}{p/g} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Trample
Whenever this Creature Mutates, put X +1/+1 counters on it, where X is the number of forests you control.
At the beginning of each upkeep, if no spells were cast this turn, double the number of counters on this Creature.