This code must be entered with the default keyboard key settings or they will not work. Press [Punch] [Senses] [Punch] [Senses] [Punch] [Punch] [Crouch] [Senses] at the main menu. The sound of a click will confirm correct code entry.
Then, press the following [Punch] [Senses] [Punch] [Senses] [Punch] [Punch] [Senses] [Crouch]. You will hear two clicks. After the second click, the "Level
Select" options should now appear instead of the "Continue" option at the main menu. Also, a cheat menu that includes an "Invincibility" option will appear when game play is paused. This unlocks everything except the Strikes.
NOTE: There are two side effects after using the level select cheat. First, stealth attacks no longer give you dog tags, which means you cannot advance to a higher strike level. Get all the tags you need before using the cheat. Secondly, when you save a game in which the level select code is used, the file is now marked with an "X" just before the time and date.