>>56092951I wouldn't make a fixed challenge mode, but would instead add in a dozen or more options and sliders to tweak all the parameters.
>exp gain rate>exp share percent>exp from wild pokemon>enemy level>ai difficulty>switch/set>trainer battles singles/doubles>pokedollar reward rate>wild pokemon encounter rate>pokemon catch rate>items in battle>items in trainer battle toggle>randomizer options for everythingBasically take any of the self imposed rules or mods from challenge mode romhacks or ironmon runs and make them options in game.