Assassination Mode
Enter SCOPE as a code to unlock Assassination Mode.

Explosive Scenery
To make the scenery, well, explosive, enter this code: BOOM.

Level Select
Enter PASSPORT as a code to unlock all of the levels in the game.

Protect Mode
Enter GUARDIAN as a code to unlock Protect Mode.

Team King of the Hill Mode
To unlock Team King of the Hill Mode, enter this code: TEAMWORK.

Uplink Mode
Enter TRANSMIT as a code to unlock Uplink Mode.

Goldeneye Strike
Enter ORBIT as a code

Get Tuxedo in MP Mode
Enter BLACKTIE as a code to unlock the Tuxedo

Get bigger clip for Sniper Rifle
Enter MAGAZINE as a code

Assasination mode
Enter SCOPE as a code

Unlock All Characters
To unlock all characters at the enter code screen type in PARTY

Chain Reaction Level
To unlock Chain Reaction Level, at the enter code screen type in MELTDOWN

Unlock Nick Nack
To unlock nick nack, at the enter code screen type in BITESIZE