I Have the Alchemy Emperor in My Head - Chapter 2445 - : I’m Your Uncle

Xiaya reincarnated in the Dragon Ball Universe as a Saiyan 12 years before the destruction of Planet Vegeta.

Watch him as he creates the strongest legend of Dragon Ball World from the beginning.

- Description from Novelupdates

220 years ago, in the legendary Dragon Demon War, Hero Azell ended the war by killing the evil Dragon Demon race’s King Atein. He was able to save the population, but as a consequence, he was cursed. While he was dying, the high magician suggested a gamble that might save his life.

The main character is reborn as a character from a game he played in his previous life. This character falls into ruin along with the villainess, spending the last of their years together. A man named Kururi Helan.

She, the prime minister’s daughter, was timid and cowardly. Because her engagement fell through, and her reputation was ruined, she was pressured to spill her own blood in the palace hall! Once again opening her eyes, the cowardice had vanished, replaced by coldness, causing others to be intimidated at first glance. Yet no one realized, she was not her.