Gisa and Geralf is a mythic Legendary Creature — Human Wizard card from Eldritch Moon (EMN), collector number 183. Current market price: $0.32 (foil $0.54), TCGplayer market prices via Scryfall.
When Gisa and Geralf enters, mill four cards. Once during each of your turns, you may cast a Zombie creature spell from your graveyard.