Throat Slitter is a uncommon Creature — Rat Ninja card from Betrayers of Kamigawa (BOK), collector number 88. Current market price: $4.07 (foil $31.25), TCGplayer market prices via Scryfall.
Ninjutsu {2}{B} ({2}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.) Whenever this creature deals combat damage to a player, destroy target nonblack creature that player controls.