All Weapons

Start a new game then pause the game and press square, circle, R1, L1, R1+R2. To get this code to work you have to enter it within two seconds.

Invincibility

Start a new game then pause it and press square, circle, L1, L1+L2.

Run Faster in Multi-Player Mode

Hold square+triangle to chase your opponent quicker in multi-player mode.

Secret Artifact

In level two kill the blue spy and pick up the information that he leaves behind. Then when you are ordered to evacuate the area ignore those orders and go to the tan post. Kill the guys there and cycle through your weapons until you see info as your weapon. Press select and read it. Then go hunting for the artifact.

Secret Key

Go to the two player level ‘Clean Up This Mess!’ and go into the closet that is located in the North East direction. You will find a key located between two books. Once you have the key look at your radar. You will then see two doors. One is the closet and the other is where you use the key you found. Take the key there. When you get close enough to it you will automatically use the key.

Level Select

At main menu press Square, Circle, R1, L1, L2, and R2.

Master cheat

This cheat lets you enable all levels, get all weapons, infinite ammo, invincibility, all objects done, and last but not least walk through anything. During the game pause the game and press L1, L2, R2, R1, Right, Up, Up, Cross, Square, Circle, Triangle.

First person view

While playing a game, hold Start + Circle + Square. Press Start to resume the game.

More tanks

Quickly press Square, Cross, Cross, R1, R2 at the main menu.

More Damage in Multiplayer

When using the flamethrower in two player mode, tap the Cross button instead of holding it. The flamethrower will then do more damage.