With no warning, the world is thrown into chaos by the sudden attack of the Mycenae Empire, led by the fearsome Great General of Darkness. As the Mazinger Army struggles against the seven powerful generals and their advanced Warrior Beasts, Archduke Gorgon relentlessly hunts down Koji Kabuto to prevent him from reaching Mazinkaiser. However, a crimson light shining over Mt. Fuji signals the dawn of an epic showdown, promising the most monumental battle in history.