Prior to the events of the anime, three factions—the Garan Army, the Kiba Army, and the Aira Army, battle for total dominance of Machine Island. The island is basically a prison, isolated from the rest of the world. The island contains a vast amount of resources, allowing the three factions to create an infinite supply of giant robots for their respective armies. The world government learns that the island's power reactor has become unstable and will explode within 66 hours, destroying all of life and Earth itself. The government sends the Death Caprice squad, composed of mercenaries Ken Kaido and Ryo Magami to solve the issue, along with their giant robot Mazinkaiser, but was that a good idea?

This is the missing Hot Springs episode included in the unrated boxset of Maze: Mega-Burst Space.

Loki, the Norse god of mischief, has been exiled to the human world for what was apparently a bad joke. Along with being exiled, he's forced to take the form of a child. He's told the only way he can get back to the world of the gods is if he can collect auras of evil that take over human hearts, and so to do this he runs a detective agency. Loki is soon joined by a human girl named Mayura who is a maniac for mysteries, and she soon helps out in her own way. However, soon other Norse gods begin to appear, and most have the intent to assassinate Loki for reasons unclear. (Source: ANN)

The villainous Dr. Hell has amassed an army of mechanical beasts in his secret hideaway, the island of Bardos located in the Aegean Sea. He is capable of controlling mechanized beasts with his cane, and instructs them to unleash devastating attacks. However, Dr. Hell doesn't do all the dirty work by himself; he has his loyal henchman Baron Ashura to carry out his devilish plans. There are also those that will see to it that evil does not prevail. Kouji Kabuto is the young and feisty teenager with a score to settle: his goal is avenging the murder of his grandfather by Dr. Hell. And he might just be able to pull it off, as he is the pilot of Mazinger Z, a mighty giant robot made out of an indestructible metal known as Super-Alloy Z. Mazinger Z boasts several powerful special attacks. By channeling Photonic Energy through its eyes, and unleashing the Koushiryoku Beam, it can cause great destruction. But things get really cool when Mazinger Z launches its Rocket Punch attack. Dr. Hell and his minions might have just found their match!