Odd-Eyes Phantom Dragon - Legendary Dragon Decks

[ Pendulum Effect ] Once per turn, when an attack is declared involving your face-up monster and an opponent's monster, if you have an "Odd-Eyes" card in your other Pendulum Zone: You can make that monster you control gain 1200 ATK until the end of the Battle Phase (even if this card leaves the field). [ Monster Effect ] When this Pendulum Summoned card inflicts battle damage to your opponent by attacking: You can inflict damage to your opponent equal to the number of "Odd-Eyes" cards in your Pendulum Zones x 1200. You can only use this effect of "Odd-Eyes Phantom Dragon" once per turn.