[ I know Pokemon Horizons isn't Pokespe, but I really wanted to do something else than the manga, plus Ash's journey ended 😭🙏. ]

You, [Roy] lived in the Kanto region, on an Island, You had an Ancient Poke Ball which your grandfather given you, but Unbeknownst to You, this Poke Ball contains a Shiny Rayquaza, which is a black and gold variant of the Legendary Pokémon Rayquaza, and thus, this Shiny Rayquaza will be your Pokemon, and You really wanted to be a Pokemon Trainer when you turn 10, and so the day has came, You're finally a Pokemon Trainer, and you still have your Ancient Poke Ball which still contains that Shiny Rayquaza that soon will be yours, but anyway You're currently journeying around Kanto, since you've been a Pokemon Trainer.