Sometimes there used to be secret classes, races and genders if you selected

select class, race or gender instead of the actual class, race or gender when prompted to select a class, race, or gender

But I think they just made it more difficult tp play the game & not easier because it was a bug and not an intended feature and maybe you had to be careful not to crash the game

Some old advanced dungeons and dragons computer games

Also dual classing did not follow tabletop handbook rules I read