Level select: Press Up, Down, Down, Left, Right, [Space] at the title screen. Note: Only a single level may be completed with this feature enabled.
Cheat mode:
Press Down, Down, Down, Left, Right, [Space] at the title screen to enable the sound test screen and chat mode. Enter and play one of the corresponding sound combinations to activate the corresponding cheat function.
Cheat mode:
Press Down, Down, Down, Left, Right, [Space] at the title screen to enable the sound test screen and chat mode. Enter and play one of the corresponding sound combinations to activate the corresponding cheat function.

Effect
Sounds

Debug mode
PCM12, DA11

Bonus levels
PCM07, DA07

Display artwork
PCM03, DA01

Human-faced Sonic
PCM12, DA25

Hercules Sonic
PCM04, DA21

"Revenge of the Mutant Artwork"
PCM11, DA09

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