Hollow Giants
Activate this card only if both players control a monster that was Special Summoned from the Extra Deck. Negate the effects of face-up monsters Special Summoned from the Extra Deck. If a monster(s) is destroyed by battle involving 2 monsters that were Special Summoned from the Extra Deck: Send this card to the GY, also the player(s) who controlled the destroyed monster(s) takes 1000 damage.