Tidal Abomination

Mutate {p/u}{p/u}{p/u} (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.)
Flash, Evolve
When this Creature Mutates, you may return up to X Creatures to their owners hands, where X is the number of islands you control.
Whenever this Creature deals combat damage to a player, put a +1/+1 counter on it.