My very first shiny encounter was a shiny Machoke in the original Pokémon Diamond game for DS. Back then when I was still a kid, I didn’t even know what shiny Pokémon were. All I knew was that a green Machoke was NOT normal. And the way it sparkled too? I HAD to catch it. So I did. Unfortunately I don’t know what happened to that game with my first ever shiny Pokémon. But it is a good memory.

Edit: I’m sorry I don’t have time to respond to everyone, but I really do enjoy reading everyone’s first shiny experiences (if you were lucky enough to have any). It’s super fun to compare to my own! The world of Pokémon within the time of our lives is interesting, and so much has changed over the years. Shinies have become easier to farm in recent games, which is sort of appreciated but also kinda kills their very rare charm. Nonetheless, they are cool and fun to talk about.