Normally you cannot change weapons except by picking up new ones. To access the weapon select screen, exit game play to the main menu, then resume the level. Note: You will only have the default amount of ammunition for the selected weapon and will lose your previous stock. You can only choose one weapon, and will lose the other two special weapons.
To unlock Challenge Mode and the following four levels, enter this code at the title screen using the Wii Remote D-pad: DOWN, UP, LEFT, RIGHT, RIGHT, LEFT. A small chime will confirm correct code entry and the game will restart:
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