Jinki: Extend

Aoba, an aspiring mecha model builder, lives with her grandmother until the latter's passing. After her grandmother's death, Aoba is taken to a secret base where she meets a massive robot. At the base, she learns that the piloted robots are fighting against Ancient-Jinki in battles staged in The Grand Savanna, but the motivations behind these conflicts are unclear. Aoba dedicates herself to training in the base's facilities in hopes of eventually piloting a robot and uncovering the truth behind these events.