MTL - Why is the Bright Moon Shining? - Chapter 30

For Cain, the promised land of opportunity in the Pokémon World was not the paradise he imagined. Instead, he fell into the hands of the sinister Team Rocket, a prisoner on an island where darkness devours hope.However, even in the most desperate moments, fate did not abandon him entirely. A strange twist brings him back to the beginning of it all, to the place where his dreams were buried under the shadows.Now, with the knowledge and scars of his previous life, Cain has the chance to correct the course of his destiny.Free from the chains of the past, he must forge his own path in a world full of mysteries and dangers. With new allies and old enemies, the battle for his freedom will not be easy, but Cain has decided that this time he will not fail. Neither against the Pokémon nor the humans who stand in his way.

He became a teacher at the best magic academy in the empire.
….For being mistaken for someone else.

As he transmigrates across the continent of Douqi, Gu He takes on the mantle of Alchemy King Gu He and gains an incredible power - the Ten Thousandfold disciple cashback system. This allows him to grant gifts to his disciples, which are then returned ten thousandfold.“You have gifted Liu Ling the Green Lotus Core Flame, triggering a tenfold return and granting you the mighty Green Lotus Holy Fire!” the system announces as each gift brings Gu He greater power.After three years of intense training, Xiao Yan returns proudly to the Yunlan Sect, eager to display his newfound strength.“Don't underestimate this once poor youth!” he warns his former lover Nalan Yanran. “Today I'll show you what a true genius can do!”But Nalan Yanran just smiles faintly. “Is that so?” she asks, as a terrifying Dou Emperor aura suddenly surges from her.Shocked, Xiao Yan stammers in disbelief, “How did you become a Dou Emperor powerhouse?”With an arrogant smile, Nalan Yanran replies, “With my master, anything is possible.”