2 Level 4 monsters
All other LIGHT monsters you control gain 500 ATK. You can only use each of the following effects of "Galaxy Photon Dragon" once per turn. You can detach 1 material from this card; take 1 "Photon" or "Galaxy" card from your Deck, and either add it to your hand or send it to the GY. If a LIGHT monster(s) that has a Level is Special Summoned to your field: You can target 1 of them; its Level becomes 4 or 8 until the end of this turn.