Invincibility
Pause then enter: Up, Down, Up, Down, Up for the cheat prompt. Then enter Right, Left, Down, Down, and Up on the D-pad.

Medal of Honor: Vanguard

Extra Armor – Pause the game and enter Up, Down, Up, Down and you will see a screen asking for your cheat code. Press Right, Left, Right, Down, Up, Right to receive extra armor.