Magma Taishi

Alien invader Goa threatens to conquer Earth, but the Murakami family refuses to surrender. After showing Atsushi, Tomoko, and their son Mamoru his power, Goa sends monstrous creatures against the planet. Earth’s defenders are Magma, a golden, armored giant, and Mol, his human-sized wife. Both were created by the wizard Earth, who lives deep beneath the planet. Magma and Mol befriend Atsushi and Mamoru, and Earth creates Gam, a duplicate of Mamoru, to be their child. Earth gives Mamoru a whistle that summons Gam, Mol, or Magma with one, two, or three blows, respectively, so they can answer when Goa’s monsters attack.