Mazinkaiser SKL - S01

Before the anime's story begins, three factions called the Garan Army, the Kiba Army, and the Aira Army are fighting for complete control of Machine Island. The island is essentially a prison, cut off from the rest of the world. It holds a huge amount of resources, which lets the three factions build an endless supply of giant robots for their armies. The world government finds out that the island's power reactor has become unstable and will explode within 66 hours, destroying all life and Earth itself. The government sends the Death Caprice squad, made up of mercenaries Ken Kaido and Ryo Magami, to fix the problem, along with their giant robot Mazinkaiser, but was that a good idea?