Enter these at the "Difficulty Select Screen" when starting a new game. After each code you should hear Red Alert say "code accepted".
Deep Amazon Level Complete: LEFT, RIGHT, LEFT, LEFT, RIGHT, R1, R2, CIRCLE
Mid Atlantic Level Complete: CIRCLE, SQUARE, CIRCLE, SQUARE, Right, Left, Left, Right
Alaska Level Complete: R1, CIRCLE, R1, SQUARE, Left, Left, Right, Left
Starship Level Complete: LEFT, LEFT, RIGHT, CIRCLE, CIRCLE, RIGHT, RIGHT, LEFT
Earth Complete: R2, R1, L1, L2, SQUARE, CIRCLE, SQUARE, CIRCLE,
At the Autobot HQ main menu screen enter the following:
Infinite stealth: (Must have convert minicon equipped): UP, UP, DOWN, DOWN, L1, L2, L1, L2
Infinite Powerlink: UP, DOWN, UP, DOWN, CIRCLE, SQUARE, SQUARE, CIRCLE
Big Head Mode: CIRCLE, CIRCLE, CIRCLE, SQUARE, L1, L1, L1, L2
Turbo Mode: L1, R2, R2, SQUARE, SQUARE, SQUARE, SQUARE, L1
One hit kills: (works on bosses to)
Pause game play, then press:square, circle,square,circle,L1(x2)
L2,L.
Note:This must be done each time you enter a new level or leave a level and ruturn.