Things You'll Need
Instructions
Progress through the game completing the levels in the single-player campaign. This can be accessed through the "Story Mode" item on the main menu.
Play through the single player game, completing the levels in the campaign by accessing "Story Mode" from the main menu. You'll need to play through the first seven areas until you gain access to "The Wilderness" area. Complete the first level "The Frozen Tundra," in order to gain access to "The Bunker."
Join the game as the second player. Start from the beginning of the level and work through until you reach the two rotating wheels with the challenge key in between them. After these wheels, but before the checkpoint, there's a small snow slope on the rearmost plane of the level. Head left on the snow slope until you reach the two-player area. One of you should hop down to the lower level and flip the lever. This will rotate the second wheel, allowing the second lever to be thrown. The player who is on the slope should now be able to hop on top. The player below throws the switch again and the upper player is lifted up further. At the top, step on the button to open the door to the prize area below. The lower player can now go inside and grab the Egg Carton, Collar and Tie, Decayed Metal Plate and Solder's Helmet.