This monster can only be Ritual Summoned with the Ritual Spell Card, 'White Dragon Ritual.' You must also Tribute monsters whose total Levels equal 4 or more from the field or your hand. When this monster attacks a face-down Defense Position monster, destroy the face-down monster with this card's effect. You can Tribute this card to Special Summon 1 'Blue-Eyes White Dragon' from your hand or your Deck. ('Blue-Eyes White Dragon' cannot attack during that turn.)