Spell Queller is a rare Creature — Spirit card from Eldritch Moon (EMN), collector number 189. Current market price: $0.40 (foil $1.59), TCGplayer market prices via Scryfall.
Flash Flying When this creature enters, exile target spell with mana value 4 or less. When this creature leaves the battlefield, the exiled card's owner may cast that card without paying its mana cost.