At the title screen, press [Down], [Down], [Down], [Left], [Right], [Space] to enable the sound test screen and chat mode. Then, enter and play one of the corresponding sound combinations to activate the corresponding cheat function:
RESULT CHEAT CODE Debug mode PCM12, DA11 Bonus levels PCM07, DA07 Human-faced Sonic PCM12, DA25 Hercules Sonic PCM04, DA21 Display artwork PCM03, DA01 "Revenge of the Mutant Artwork" PCM11, DA09
At the title screen, press [Up], [Down], [Down], [Left], [Right], [Space]. Note: Only a single level may be completed with this feature enabled.
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