Great Mazinger vs. Getter Robo G: The Great Space Encounter

An extraterrestrial craft breaches Earth, descending upon the Getter Institute to strike; Getter Robo is mobilized to intercept, yet the UFO and its colossal space-born monsters prove overwhelming for the Getter squad. Not only is Getter Robo defeated, but Ouishan falls in combat. With Getter Robo sidelined, the world's only hope appears to be Great Mazinger, but the aliens' power might also be too much for even him. Can Dr. Saotome forge a new Getter Robo in time to help save Great Mazinger, Japan, and the entire world?