Gundam Build Fighters: GM's Counterattack

Nils Neilsen invites Sei Iori, Meijin Kawaguchi and the rest of the group to Yajima Stadium in order to try out his new large-scale battle system. Sei is just about to unveil the improvements he's made to his Gunpla, when a mysterious group appears and challenges them all to a Gunpla Battle!