I couldn't find out how to do it. Apparentely it's possible and super simple, but when i try to just edit the hex files it gets corrupted.
Can someone explain me how to do it? First time trying to mod something, and i have absolutely no idea what i'm doing, as I didn't find a tutorial that explained it.

I opened "PARAM(dot)SFO" with a hex editor, but if I edit it the data gets corrupted.
I'd like to add some coins, but even if i change it from 0 to 1 it doesn't work.