Brokkos, Apex of Forever is a mythic Legendary Creature — Nightmare Beast Elemental card from Magic Online Promos (PRM), collector number 80987.
Mutate {2}{U/B}{G}{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 You may cast this card from your graveyard using its mutate ability.