The cheat is different every time you pause the game.



        Pause the game and press the buttons.  You should notice that one

        of the buttons will produce a sound with a higher pitch.  Now press

        another button.  If you don't get another high pitched sound press

        the button that first made the sound and continue to try the other

        buttons.  The cheat is a sequence of 5 or 6 buttons.  Just think of

        the game SIMON and remember the sequence until you get it right.

        You will hear a different sound when you complete the sequence.


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ADDITIONAL CHEATS (from OLLIVision)

To get all weapons, after the intro (during the flight sequence), enter
one of these button combinations on the joypad:

- YELLOW - RED - YELLOW - DOWN - GREEN - RIGHT - RED - UP
- RED - GREEN - BLUE - YELLOW - DOWN - DOWN - BLUE - DOWN - RIGHT - BLUE
- YELLOW - RED - GREEN - BLUE - UP - LEFT
- BLUE - YELLOW - RED - GREEN - BLUE - LEFT