Kai Toshiki's search for Aichi, the hero who saved the world from Link Joker, is complicated by his sudden disappearance and the loss of everyone's memories about him. Kai's search is the only hint he has, along with the deck of Royal Paladin and the Blaster Blade, which he uses to continue the fight. Kai is approached by the Quatre Knights, four powerful vanguard fighters with mysterious abilities who urge him to give up the search. With the new power of Legion, Kai fights on to find Aichi.