Stab Wound is a uncommon Enchantment — Aura card from Magic 2015 (M15), collector number 116. Current market price: $0.19 (foil $0.20), TCGplayer market prices via Scryfall.
Enchant creature Enchanted creature gets -2/-2. At the beginning of the upkeep of enchanted creature's controller, that player loses 2 life.