Rem Karolus, Stalwart Slayer is a rare Legendary Creature — Human Knight card from Innistrad: Double Feature (DBL), collector number 235. Current market price: $0.48 (foil $3.13), TCGplayer market prices via Scryfall.
Flying, haste If a spell would deal damage to you or another permanent you control, prevent that damage. If a spell would deal damage to an opponent or a permanent an opponent controls, it deals that much damage plus 1 instead.