BGM Test option:
Beat the game to unlock the BGM Test option.
New Game mode:
Beat the game and load your cleared saved game file to start a new game session with all previously obtained items and weapons, as well as your money. Additionally, an extra chapter will be available. Complete the conversation with Cindy at the Dragon Tower before the Prologue 1. The red orb in the dragon’s mouth will now be broken, allowing you to access a new, difficult area.