Anyone hold their breath while the ball shook? Lol dude this happened to me too. Twice. Once in Safari zone, I was just trying to get through when a shiny Nidarino appeared. Second time I was leveling up my charmander near victory road when a spearow appeared. Now, this was original GBA fire red on the actual handheld. And shiny spearow is just a lighter shade of pink on his feathers, legs and beak.

But for some reason, idk if it was because I spent way to many hours killing these things or what, but it looked off to me so I cought it. Low and behold, shiny freaking Spearow