Keroro Gunsou Movie 3: Tenkuu Daikessen de Arimasu!

During an expedition to the ruins of Machu Picchu, Keroro accidentally activates an ancient mechanism built around a mysterious blue crystal. The platoon escapes the collapsing chamber, but Keroro leaves his Kero Ball behind, while Fuyuki briefly sees a strange glowing girl watching them.

Back home, a new threat appears in the form of another Keroro who commands a powerful airborne fortress and seems determined to conquer Earth properly. The real Keroro must face a rival who looks like him but possesses everything his own invasion usually lacks: discipline, power, and a frighteningly effective plan.