Cannot be Normal Summoned/Set. Must first be Special Summoned (from your hand) while you control a "Photon" or "Galaxy" monster. Cannot attack the turn it is Special Summoned. You can only Special Summon "Photon Vanisher(s)" once per turn. If this card is Special Summoned: You can add 1 "Galaxy-Eyes Photon Dragon" from your Deck to your hand. An Xyz Monster that was Summoned using this card on the field as material gains this effect.