Intel Pieces
Below is the level distribution list for Intel Pieces!
Intel Pieces are enemy laptops full of information found throughout the game. There are 30 of them total.

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

Cheat List
Cheats are not unlocked by inserting cheat codes! They are unlocked by acquiring Intel Pieces. Intel Pieces are enemy laptops full of information found throughout the game. The more of them you collect, the more cheats you can access.

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

New Mission
Description: Play an extra mission after the main quest is completed,
How to unlock: Beat the game and view the ending credits. Then you will be able to play one last single player mission.

Arcade Mode
Description: Arcade Mode itself is split into two options - Full Challenge or Level Challenge - they basically add extra replayability to the game.
How to unlock: Beat the game once through on any difficulty level.

Prestige Mode
How to unlock Prestige Mode: (multiplayer-only mode) you must reach experience level 55. 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 10 times, giving you 10 different icons in in-game lobbies to show your extreme achievement.