Nils Nielsen extends an invitation to Sei Iori, Meijin Kawaguchi and other guests for an exhibition battle showcasing his new, advanced battle system as Yajima Stadium nears its completion ceremony. As they converge, Sei intends to display his enhanced Build Strike Cosmos, only to realize that an essential element is absent. Meanwhile, a stranger covertly infiltrates the stadium's networks, ensnaring Sei and his associates within. The anonymous adversary extends an invitation to a Gunpla Battle and divulges a puzzling agenda.