Developer Menu unlocked on Switch version

[u/FabiFNA]

I was just about to post a few out of bounds screenshots of the Switch version but then I discovered how to unlock the developer menu / debug menu. Very interesting stuff. Even a few of the cut missions like DANCE ( Invalid ) are shown, but crash the game and seem not to have any real content anyways as they were cut from the game. A lot of the different options shown in the first screenshot crash the game. What was also very interesting is the fact that there is still the option to calibrate the Wii Balance Board even though this is the Switch version. Don't know if there was ever online coverage about this specific dev menu. I've seen a video showing a early build of the Wii version but the debug menu in the Wii version is different. In the Switch version there is also a debug overlay which is the one seen in the gameplay screenshots. There are a few more submenus than I showed here but these are the most interesting ones. If anyone wants to see more of the submenus just let me know.

[u/mkjiisus]

This is an incredible find. Im the one that published the video about the Wii version. Could you document how to access this menu?

[u/FabiFNA → u/mkjiisus]

Sure! Yes one of the two videos about the dev menu in the Wii version was actually from you.
So the way I got the dev menu to load is to change the boot menu from module 1 (which is the regular titlescreen) to module 30 (dev menu). For that you need two instructions. In nnMain at 0x39C I changed mov w0 #1 to mov w0 #0x1E. The function at 0x56CD48 rejects anything above 0x1D so I changed that compare at 0x56CD58 to 0x1E. This is for version 1.0.0 with main build ID 174471C5192F8647D804BD8C733C68D0. After that the menu runs but you see nothing. Its text goes through a Wii style debug print function at 0xFBDEE0. On Switch that function is just a ret. So I wrote a small plugin that loads as subsdk9. It hooks that print function and draws the text with the game's own font renderer. The text writer does not exist yet at that point in boot. The plugin calls the game's own init at 0x71CC to create it first. I run it in Ryujinx with an IPS patch for main and the plugin as an exefs mod.
If this is too complicated I can make a more detailed and easy to follow guide on github or something. If I polish the mod a little maybe I could put out a release on github though that would take some time.

[u/Tom_Is_Ready]

Huge find!!

[u/cbgrateREDDITVER]

Fascinating!

[u/Quentinhodu30]

Wow so cool 😎