Cacophony Scamp is a uncommon Creature — Phyrexian Goblin Warrior card from Phyrexia: All Will Be One (ONE), collector number 124. Current market price: $0.29 (foil $0.33), TCGplayer market prices via Scryfall.
Whenever this creature deals combat damage to a player, you may sacrifice it. If you do, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.) When this creature dies, it deals damage equal to its power to any target.