Snapping Thragg is a uncommon Creature — Beast card from Onslaught (ONS), collector number 233. Current market price: $0.07 (foil $0.65), TCGplayer market prices via Scryfall.
Whenever this creature deals combat damage to a player, you may have it deal 3 damage to target creature that player controls. Morph {4}{R}{R} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)