The Getter Navalon Gun is a defense weapon for the Saotome Institute in the anime. It is a mounted gun built on the center of the Institute building. It served as a major plot element during when the Empire attacked the institute directly including the final battle where it was destroyed.
While built for defense, the Getter Navalon Gun is able to destroy a Mechasaurus in just one blow as the primary gun is powered by Getter Rays. A special turret mode also exists using shells designed by Bunji Daiko to attack multiple enemies.