Fate/Zelretch: Union Alternative

The Multiverse. The concept of multiple universes where infinite possibilities lead to their creation. Each universe has its own stories. Its own heroes. And its own villains. But sometimes, multiple universes can collide together, having the same heroes and the same villains but a whole new story.

But the multiverse that contains this story is in grave danger. Across the Omniverse, the concept of infinite universes, a similar problem has been occurring. With the collision of multiple universes, such as the Worlds of Grimm, Quirks, and DXD, the "World of Union" is born. But this new world is no miracle; it is a living nightmare. In these worlds, heroes are the villains; and those who become their victims become just as guilty as them, creating an endless spiral of chaos, bloodshed, and suffering.

The Kaleidoscope and the Wizard Marshall of the World of Magus, Kischur Zelretch Schweinorg, has observed these destructive worlds for a long time, but has finally found the root of this madness. To bring peace and balance to the Omniverse and assure the safety of his Multiverse, what does he do?

He sends his son to investigate.

This is the story of the Son of Zelretch and his journey to find the truth behind Union Academy's creation and to defy fate once again.

Note: This will be a crossover between multiple anime and a few video game franchises. These franchises will be added to the tags as I introduce them. There will be a few mentioning comic book stuff, but that will be it.