Massacre Girl is a mythic Legendary Creature — Human Assassin card from Marvel Universe (MAR), collector number 67. Current market price: $1.21 (foil $3.30), TCGplayer market prices via Scryfall.
Menace When Massacre Girl enters, each other creature gets -1/-1 until end of turn. Whenever a creature dies this turn, each creature other than Massacre Girl gets -1/-1 until end of turn.