How to make secret codes to select characters

[MyztikSpark]

I want to know how to make secret codes to select characters, like how you select Shin Akuma in Street Fighter Alpha 2.
If there is anyway, please let me know.

[Basara Bogard]

AFAIK, it's impossible to make something like this in MUGEN, and if it's possible, probably could be done in a close fullgame. The only thing I've seen something like that is in UFGE, another fighting game engine (even previous to MUGEN) that has this in their fullgames, where you can unlock characters with a code.

Not sure if this can be done even on IKEMEN, but it's a feature I'd like to see in MUGEN some time...