I have an Apocalypse City - Chapter 355 - : Wrath of the Fire God

Zhou Donghuang, a man from the Earth, is able to destroy any planet in the universe without lifting a finger. His supreme will can sweep across the vast cosmos in the blink of an eye. And his immortal spirit can depart from his body and wander around the universe!

In Kunlun Mountains lies a circular slate, which brought him back to one thousand years ago…

- Description from Novelupdates

After dying in laboratory tests, Klaus transmigrated to a Sorcerer World, in a strange and peculiar character whose existence is an enigma. He knew this world, for it was the world of the novel one of his students wrote. He also knew the character because he created it. But it was a discarded character; it never appeared in the novel. How could he have transmigrated in it? Reality hit him soon after when he was sent to cross through the first test that every sorcerer must pass to awaken his abilities. There, he will have to fight against powerful monsters, which they call Curses, and against other Sorcerers, all to try to enter the select group of Sorcerers to discover the secrets that await in this world and understand his arrival to this and his existence. Just when he thought his journey might be boring, he received a peculiar and mighty power bordering divinity, capable of making him reach unimaginable heights. Although a bit dangerous...

Once upon a time, a boy was referred to as a “War Hero.”

In another world called Aletia, the boy who had saved the Lost Kingdom, conquered their neighbouring countries, and led to the rise of a grand empire decided to throw everything away, returning to the modern era at the cost of his memories.

As three years passed, the boy who was happily enjoying his daily life was once again called back to the other world.

However, what awaited him was the Aletia of 1000 years in the future.

As his past glories became a “myth,” the legend of the youth referred to as the, “Twin Black Hero King,” begins.