Having achieved their first victory in the practice match with Gyanko, the Try Fighters are training hard for the regional qualifiers which will be held in one month. Fumina is thinking of building a new mobile suit for use in the tournament, and when she confers with Mr. Ral, he suggests that she and Sekai take a trip to G-Muse. Here, Fumina virtually goes into a trance as she tries to choose a Gunpla, and Sekai is soon bored of watching her. A clerk encourages Sekai to build his first Gunpla, the Musha Godmaru, which he uses to battle some little kids. As Fumina rejoins him, they encounter Minato Sakai, a middle-school builder from Osaka. In the twinkling of an eye, Minato builds his own Kouki Gundam and begins a battle with Sekai. Thanks to his knowledge of SD Gundams' unique traits, Minato gives Sekai a hard fight and ultimately defeats him. But this battle has given Sekai and Fumina some valuable ideas for the tournament.