Army Men - Operation Meltdown - PlayStation 1
Type in the following codes at the main menu screen:
INVISIBLE PLAYER
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Press: R1, L1, X, circle X2, square X2, R1, circle.
UNLOCK ALL WEAPONS
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Press: X x2, triangle, circle, up X2, down, square, triangle.
LEVEL SELECT
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Press: R1+R2, L1+L2, circle, square.
INVISIBLE PLAYER
----------------
Press: R1, L1, X, circle X2, square X2, R1, circle.
UNLOCK ALL WEAPONS
------------------
Press: X x2, triangle, circle, up X2, down, square, triangle.
LEVEL SELECT
------------
Press: R1+R2, L1+L2, circle, square.