Cemetery Prowler is a mythic Creature — Wolf card from Innistrad: Double Feature (DBL), collector number 458. Current market price: $11.24 (foil $38.07), TCGplayer market prices via Scryfall.
Vigilance Whenever this creature enters or attacks, exile a card from a graveyard. Spells you cast cost {1} less to cast for each card type they share with cards exiled with this creature.