Narset, Enlightened Exile is a mythic Legendary Creature — Human Monk card from March of the Machine: The Aftermath (MAT), collector number 173. Current market price: $10.62 (foil $17.23), TCGplayer market prices via Scryfall.
Creatures you control have prowess. Whenever Narset attacks, exile target noncreature, nonland card with mana value less than Narset's power from a graveyard and copy it. You may cast the copy without paying its mana cost.