Kess, Dissident Mage is a mythic Legendary Creature — Human Wizard card from Secret Lair Drop (SLD), collector number 1167. Current market price: $17.71 (foil $18.87), TCGplayer market prices via Scryfall.
Flying Once during each of your turns, you may cast an instant or sorcery spell from your graveyard. If a spell cast this way would be put into your graveyard, exile it instead.