Cheats are unlocked not by inserting passwords, but by acquiring the thirty Intel Pieces strewn throughout the game. The more of them you collect, the more cheats you can access. On the left are the number of Intel Pieces collected, and on the right are the cheats that are unlocked, with an explanation of what each does.

• 2 - "CoD Noir" Play the game in black and white.
• 4 - "Photo-Negative" Game colors become inverted.
• 6 - "Super Contrast" Game's contrast increases.
• 8 - "Ragtime Warfare" The game feels like an old silent movie.
• 10 - "Cluster Bombs" One frag grenade thrown equals five in explosion.
• 15 - "A Bad Year" Enemies explode into tires when shot.
• 20 - "Slow-Mo Ability" Game plays at 40% normal speed.
• 30 - "Infinite Ammo" Just what it says.

To unlock Arcade Mode, beat the game once through on any difficulty level. Arcade Mode itself is split into two options - Full Challenge or Level Challenge - that add extra replayability to the game.

To unlock Prestige Mode, which is a multiplayer-only mode, you must reach experience level fifty-five. Instead of capping out at level fifty-five, which is the highest level, Prestige Mode allows you to start again from level one. This can be done a total of ten times, giving you ten different icons in in-game lobbies to show your extreme achievement.

To play an all-new mission, which is an extra mission after the main quest is completed, beat the game and view the ending credits thereafter. After they've run their course, you will then be given the opportunity to play one last single player mission before all is said and done.

To unlock the following weapons in multiplayer mode, reach the numbered rank listed.

• Assault Rifle (G3) - Rank 25
• Assault Rifle (G36C) - Rank 37
• Assault Rifle (M14) - Rank 46
• Assault Rifle (M4) - Rank 10
• Assault Rifle (MP44) - Rank 52
• LMG (M60E4) - Rank 19
• Pistol (Desert Eagle) - Rank 43
• Pistol (Golden Desert Eagle) - Rank 55
• Pistol (M1911) - Rank 16
• Shotgun (M1014) - Rank 31
• SMG (AK-74U) - Rank 28
• SMG (Mini Uzi) - Rank 13
• SMG (P90) - Rank 40
• Sniper Rifle (Barret) - Rank 49
• Sniper Rifle (Dragunov) - Rank 22
• Sniper Rifle (M40) - Rank 04
• Sniper Rifle (R700) - Rank 34

To unlock the following "Golden" weapons, fulfill the requirement listed.

• AK-47 - Complete all Assault Rifle challenges
• Desert Eagle - Attain Level 55
• Dragonuv - Complete all Sniper Rifle challenges
• M1014 - Complete all Shotgun challenges
• M60 - Complete all LMG challenges
• Mini-Uzi - Complete all SMG challenges

Below is the level distribution list for Intel Pieces, which are enemy laptops full of information strewn throughout the game. There are thirty of them total. The left column is the level in question, while the right column is how many Intel Pieces can be found on that level. Levels with no Intel Pieces are excluded completely.

• Level 2 - 2
• Level 4 - 2
• Level 5 - 3
• Level 6 - 2
• Level 7 - 2
• Level 9 - 3
• Level 10 - 2
• Level 12 - 2
• Level 13 - 3
• Level 14 - 2
• Level 16 - 2
• Level 17 - 1
• Level 18 - 2
• Level 19 - 2

If you have a pair of Xbox Live accounts, you can try this technique. If one account is of a lower rank than the other, you can give the lower account an instant power-up when using both accounts to play. When you unlock something at the end of the game (such as the Overkill Perk), immediately log out of your account and sign into the lesser account. Head to the Xbox Live game lobby and press Y, and the game will have unlocked for this particular account whatever you unlocked with the first account.

Attain the rank listed below for the desired picture:

• 1 - Gold shield with silver eagle in the middle
• 2 - Blue titanic diamond with star spikes on the outside
• 3 - Emerald in the middle with four lines with circles on the ends
• 4 - Black circle in the middle with white, gold, marroon and tan outsides
• 5 - Pineapple with one eye in the middle
• 6 - Gold eagle in the middle with lines such as the 3rd symbol but 6 instead of 3
• 7 - Cross but thin and look like wings with smaller wings on the outside and a square gold lined sheet in the middle
• 8 - Red diamond in middle with a triangle shield on the outside with gold and white trim
• 9 - Maroon and black Star of David
• 10 - Gold iron cross