yo /vp/, I have an action replay and I wanna utilize it to make my nuzlocke more enjoyable on slow cartridge game.

I was wondering if there is a code that makes it so you can change the shiny rate rather than guaranteeing it to be shiny?

For instance I want to run soul silver with a 1/250 ish chance of shiny. I'm having trouble finding it through google it seems as though everyone just wants the 100% shiny.

Thanks in advance