Getter Robo

From deep within the Earth's surface, the Dinosaur Kingdom make their move to wipe out mankind and conquer the planet with their mechanical dinosaurs. After a prototype Getter Robo is shot down by a mechanical dinosaur, the Saotome Research Institute decides to use the real Getter Robo, which is combat-capable. Due to a lack of pilots in the institute, Ryo Nagare goes to his college to persuade martial artist Musashi Tomoe and outcast Hayato Jin to join him and pilot the Getter Machines to combat the new threat and protect mankind. (Source: Anime News Network)

The King of Braves: GaoGaiGar

In the year 2005, a race of alien monsters called Zonders emerge from underground and launch a series of attacks on the city of Tokyo. The only defense against these creatures is the secret agency known as the Gutsy Geoid Guard (or 3G) and their ultimate weapon, the awesome giant robot GaoGaiGar. GaoGaiGar's pilot, Guy Shishio, is a former astronaut who was nearly killed two years before when the Zonders first crashed to earth. Guy's life was spared when a mysterious robot lion called Galeon pulled him from the burning shuttle and brought him to Earth. Guy's father, Leo, then used Galeon's technology to rebuild his shattered son as a cyborg, in the hopes that he could stop the aliens when they appear. Now, with Galeon as its core, GaoGaiGar fights to protect Earth. He is aided by a team of transforming robots and by a young boy named Mamoru, who has the power to purify the Zonders' cores, and seems to be connected to the mysterious Galeon. (Source: Anime News Network)