Having recovered from his battle with Adou, Sekai heads for the Labs' workshop to repair the Build Burning Gundam, and encounters a mysterious girl. Thanks to the girl's advice, Sekai finishes repairing the Build Burning, and the next day he goes to the Labs' battle room with Mr. Ral for special training. There he meets Kei Karima from Honmoku Academy, representing Kanagawa, who suggests they play a practice match. His goal is to learn the strength of the Gunpla Academy, and when Sekai realizes this, he cannot hide his anger. At this point Wilfrid Kijima, the ace of the Gunpla Academy, intervenes, as does the Gabai Institute team that represents Kagoshima. It seems the situation will get out of hand, until Meijin Kawaguchi suddenly appears on top of the battle system. Thus begins a Battle Royal among representatives of each school, under the Meijin's supervision.