Guardian of the Forgotten (Modern Horizons 3)

Creature Ñ Elephant Warrior - Vigilance
Whenever a modified creature you control dies, manifest the top card of your library. (Equipment, Auras you control, and counters are modifications. To manifest a card, put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)