This Kiruru is rather the ruins of the Machu Pichu, and where Dark Keroro was made. Before the ending of the movie, the third generation Kiruru appears to be an embryo state, the ruins were made to have warp doors leading to the ruins. Initially there was the Miruru key inside the crystal, sealing Kiruru. However, Keroro, out of curiosity, pushed the key in, and thus, reviving Kiruru. Unlike the previous generations that are to destroy, this Kiruru emphasises on invasion.