How to Unlock Debug Mode Unfortunately, the first time you play Sonic Mania, Debug Mode will not be unlocked. Doing so requires that you play the game and complete Blue Sphere stages.

Basically what I'm saying is - Debug mode is in, you filthy cheats. There's also a bunch of other Sonic Mania cheats and unlockables for Mania Mode in both the original release and Plus.

How to access Sonic Mania’s sound test Once you’re in the level select, simply scroll to the bottom and you’ll have access to Sonic Mania’s sound test. How to access Sonic Mania’s debug mode ...