The peace never lasts. Wataru thought he was done being a hero, thought he could just be a kid again, but the world won't let him rest, and the show knows that's the real cost of being chosen. Doakudar's brother isn't just a stronger version of the last threat; he's proof that victory doesn't close doors, it opens them onto harder questions. A boy who wants to go home discovers that home stopped being a place the moment he learned what he could do.
Wataru thought his adventure was over. Back on Earth living a normal life, he's content to leave the magical world behind until Ryujinmaru suddenly reappears with urgent news. The Seven Stars Mountains, the source of all light in the celestial realm, are falling under the control of Doakudar's brother, a threat even more formidable than the last. Without intervention, darkness will consume everything, trapping the magical world in eternal night. Reluctantly pulled back into action, Wataru must journey across seven treacherous star systems, each presenting new challenges and mysteries. His growth since the first battle matters now more than ever. Alongside old allies and new companions, he'll push his skills and his mechanical guardian to their limits against an enemy who's studied his methods and improved upon them. What begins as a simple rescue mission becomes a race against encroaching shadows. The stakes are higher, the enemy sharper, and the road longer than before. Wataru discovers that heroism isn't always about choosing adventure, sometimes it's about answering the call when the world needs you again.