Blood-Cursed Knight is a uncommon Creature — Vampire Knight card from Magic Origins (ORI), collector number 211. Current market price: $0.17 (foil $0.47), TCGplayer market prices via Scryfall.
As long as you control an enchantment, this creature gets +1/+1 and has lifelink. (Damage dealt by this creature also causes you to gain that much life.)