Godai Kamon wakes up with a gaping hole in his memory. He can't recall his past with B-Daman, the marble-shooting sport that defines his world, or much about his own family. Only his sister Aona remains a constant in his life. When a strange energy called the B-Crystal begins destabilizing across Crest Land, Kamon stumbles into a local B-Daman shop and meets Galvan, a B-Daman that stirs something deep within him, something he can't quite name. Partnering with Galvan feels right in a way Kamon can't explain, and he finds himself drawn back into the competitive B-Daman circuit. As he battles opponents and searches for answers, fragments of his forgotten past begin surfacing. The deeper Kamon digs, the more he realizes his amnesia isn't random. Something larger connects his lost memories to the B-Crystal's rampage, and uncovering the truth might be the only way to save Crest Land from collapse.