Yamato Delgado dreams of playing B-Daman, the ancient sport of the B-DaWorld—and his dream comes true when he's chosen to wield Cobalt Blade, the most powerful B-Daman ever. Yamato must use Cobalt Blade to compete in B-Daman tournaments and defeat the evil B-Daplayers of the Shadow Alliance, who will stop at nothing to take over the B-DaWorld. Yamato will also meet characters both familiar and unknown on his journeys, including the warm-hearted Alan and the sinister-looking Goblin. Only a few have what it takes to become a B-Daplayer; will Yamato become the B-Dachampion?