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Synopsis

Transported a thousand years into the past, he finds himself in a world of Pokémon—but not the kind he imagined. This ancient Pokémon world is dark and brutal, where Pokémon are known as "magical beasts" and constant conflict rages between humans and these creatures. Now a humble farm owner, Aven must use his knowledge of modern Pokémon science to survive.

Watch as he cultivates the land with fertilizers, breeds powerful Pokémon, crafts Poké Balls, develops technology, and lays the foundation for a new world order. For most transmigrators, science is the greatest productive force—but here, it's Pokémon who hold that title.

This is the story of a Pokémon breeder quietly farming his way to power, eventually founding the Pokémon League in an ancient world.
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Ok, I changed it from Hisui to Ancient World (Sinnoh) because the author wrote this in 2021 way ahead of Pokemon Legend: Arceus which was released on Jan 2022, but hey the story is still pretty good and the author managed to guess most pokemon found in the game except for their new regional forms.

Pokemon: The Breeder's Farming Journey to Modernizing an Ancient World

<p>Skip this chapter, was an author note chapter.</p>

Skip Chapter 107