Cheat mode:
Fire and reload the lightgun or controller at a blank portion of the main menu (or off the screen completely) to spell out the code words. The number of times Fire is pressed corresponds to a letter in the alphabet, with 1 being the equivalent of "A" through 26 being the equivalent of "Z". Press Reload to move on to the next letter. .

Master code:
Enter "MEBIGCHEAT" as a code. Press Fire(13), Reload, Fire(5), Reload, Fire(2), Reload, Fire(9), Reload, Fire(7), Reload, Fire(3), Reload, Fire(8), Reload, Fire(5), Reload, Fire, Reload, Fire(20), Reload at the main menu. The screen will flash to confirm correct code entry

Arcade mode:
Enter "BLAM" as a code. Press Fire(2), Reload, Fire(12), Reload, Fire, Reload, Fire(13), Reload at the main menu. The screen will flash to confirm correct code entry The "Arcade Mode" option will now be unlocked in the extras menu. Alternately, successfully complete the game.

Country challenges:
Enter "ABROAD" as a code. Press Fire, Reload, Fire(2), Reload, Fire(18), Reload, Fire(15), Reload, Fire, Reload, Fire(4), Reload at the main menu.

Mighty Joe Jupiter mini-games:
Enter "MIGHTIER" as a code. Press Fire(13), Reload, Fire(9), Reload, Fire(7), Reload, Fire(8), Reload, Fire(20), Reload, Fire(9), Reload, Fire(5), Reload, Fire(18), Reload at the main menu.

Alternately, successfully complete all Mighty levels in cadet training mode to unlock the "Mighty Joe Jupiter Trilogy" option in Mighty Joe Jupiter mode. Complete the easy levels in cadet training mode to unlock Mighty Joe Jupiter Episode 2. Complete the normal levels in cadet training mode to unlock Mighty Joe Jupiter Episode 3.

Jukebox and music test:
Enter "LETSBOOGIE" as a code. Press Fire(12), Reload, Fire(5), Reload, Fire(20), Reload, Fire(19), Reload, Fire(15), Reload, Fire(15), Reload, Fire(7), Reload, Fire(9), Reload at the main menu.

Alternately, successfully complete all episodes in the Mighty Joe Jupiter Trilogy to unlock the "Music Jukebox" option at the Options screen.

Ending bonuses:
Successfully complete the game to unlock the "Arcade Mode" option at the extra menu and the "Mirror Mode" option at the arcade mode menu.

Machine gun:
Successfully complete the game in arcade mode using the pistol. Start a new game in arcade mode to use the machine gun.

Cane gun:
Successfully complete the game in arcade mode using the machine gun. Start a new game in arcade mode to use the cane gun.

Shotgun:
Successfully complete the game in arcade mode using the cane gun. Start a new game in arcade mode to use the shotgun.

Hyper Arcade mode:
Successfully complete the game in arcade mode using the shotgun to unlock the "Hyper Arcade Mode" option at the arcade mode menu.

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