Unlock Sound Test Mode
Complete the game with the good ending to unlock Sound Test mode.
100% success rate. 

Maxim Kischine
Enter 'MAXIM' as a name after completing the game at least once.
100% success rate. 

Unlock Boss Rush Mode
Complete the game to unlock the Boss Rush option. There are three levels (easy, normal, and hard) that must be unlocked by playing each in succession.
100% success rate. 

Hard Mode
Enter 'HARDGAME' as a name after completing the game at least once.

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