In the Wario Land 4 code a beta logo was found by Racoon Sam and Linkin800 from the JUL Forum found some more unused tiles and a beta test level! As Linkin wrote in his topic, the test level is “surprisingly similar to the Metriod Fusion one, but thats because MF was built off of WL4’s engine”. You can read the original topic in here! There are even some debug rooms hidden in the game’s code.
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