The Main Cheats
If you own "Transformers: The Game" for the Wii, Xbox, Xbox 360, PlayStation 2 or PlayStation 3, you can enter cheats on the main menu screen. Press "Left, Left, Up, Left, Right, Down, Right" you will become invincible for the entire game. Press "Up, Down, Left, Right, Up, Up, Down" for unlimited ammunition. If you press "Down, Up, Left, Right, Right, Right, Up, Down" you will unlock all of the missions -- or levels -- within the game, allowing you to jump ahead to whatever level you choose. Pressing "Right, Left, Right, Left, Right, Left, Right" will eliminate all police cars, military vehicles and pedestrian vehicles from the roads.
The Autobots
During the main menu of the game -- regardless of which console you have -- you can change the look of specific Autobots to resemble their appearance in the cartoon as compared to the Michael Bay movie. Press "Down, Right, Left, Up, Down, Down, Left" to unlock the cartoon version of Optimus Prime. Press "Left, Up, Down, Down, Left, Up, Right" to unlock the first generation of Jazz. The screen will flash if the codes have been entered properly. Next, click on the "Bonus Features" option from the main menu and select the new look of your Autobot character.
The Decepticons
The Decepticons in "Transformers: The Game" can also have their skins -- or appearances -- altered. These codes work for any version of the game. Press "Down, Left, Left, Down, Right, Right, Up" on the main menu screen and you will unlock the cartoon Megatron. Press "Right, Down, Left, Left, Down, Up, Up" to unlock the first-generation model of Starscream, Megatron's second-in-command. Like the Autobots, you must select the "Bonus Features" option from the main menu to activate the altered Decepticons. Again, the screen will flash after you enter the codes if you've done it properly.
Other
On the main menu screen of "Transformers: The Game," press "Down, Down, Up, Up, Right, Right, Right" and you will unlock the Robo-vision Optimus Prime, another skin type for Optimus Prime. Access the "Bonus Features" option from the main menu and select "Generation 1" to play as Robo-vision Optimus Prime. You can unlock two Cybertron missions from the main menu by entering "Right, Up, Up, Down, Right, Left, Left." As with the other cheats, the screen should flash if the code has been entered correctly.