In 2021, the game's debug menu was discovered on a demo disc and was later executed in the retail version through the creation of a GameShark code. The menu contains four options featuring the surnames of four of the game's programmers (most likely to test out certain aspects of the game each one focused on more easily): Satoshi Kishiwada, Yasuhiro Yamamoto, Tamotsu Goto, and Naoto Uenaka.

Additionally, by selecting "Area 7 Action" and "Scene 06 - Last-Scene", you can access a beta version of the crumbling Soda Fountain, the final area of the game Spoiler:where Musashi battles against Dark Lumina, lacking textures and featuring an overhead camera compared to the sidescrolling camera in the final game.
Contributed by MehDeletingLater
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