Conquerer of Three Worlds Ragnaraku is a 5-cost Purple event from Memorial Collection (039), C rarity. Effect: [Main] DON!! −1 (You may return the specified number of DON!! cards from your field to your DON!! deck.): K.O. up to 1 of your opponent's Characters with a cost of 8 or less. [Trigger] Add up to 1 DON!! card from your DON!! deck and set it as active. The Four Emperors/Animal Kingdom Pirates