Mudbutton Cursetosser is a uncommon Creature — Goblin Warlock card from Lorwyn Eclipsed (ECL), collector number 112. Current market price: $0.22 (foil $0.35), TCGplayer market prices via Scryfall.
As an additional cost to cast this spell, behold a Goblin or pay {2}. (To behold a Goblin, choose a Goblin you control or reveal a Goblin card from your hand.) This creature can't block. When this creature dies, destroy target creature an opponent controls with power 2 or less.