Gagagarush (REDU-EN067) - Return of the Duelist Unlimited

When a face-up "Gagaga" monster(s) you control is targeted by the effects of an opponent's monster: Negate the effect of that opponent's monster; and if you do, destroy it; then inflict damage to your opponent equal to the destroyed monster's ATK or DEF in the Graveyard (whichever is higher).