Regeltext

Cannot be Normal Summoned/Set. Must be Special Summoned by its own effect. If "The Winged Dragon of Ra" is sent from the field to your GY while this card is in your GY: Special Summon this card. Cards and effects cannot be activated in response to this effect's activation. Unaffected by other cards' effects. You can pay 1000 LP; send 1 monster on the field to the GY. Once per turn, during the End Phase: Send this card to the GY, and if you do, Special Summon 1 "The Winged Dragon of Ra - Sphere Mode" from your hand, Deck, or GY, ignoring its Summoning conditions.