After a peaceful period on Earth following his victory over Doakudar, Wataru is summoned back into action by Ryujinmaru to combat a new threat. Doakudar's brother, Doakadar, has seized control of the 7 Stars Mountain, endangering Mt. Soukai's rainbow and plunging the world into eternal darkness if left unchecked. Wataru must embark on a perilous journey through the 7 stars system once more to vanquish this formidable adversary and save his world from impending doom.