# Completion bonusesSuccessfully complete the game on any difficulty to unlock the cheat menu and Arcade mode. The cheat menu can be found at the options menu while playing the game.
# Cheat options
Collect the indicated number of Intel pieces (enemy laptop computers) hidden throughout the game to unlock the corresponding cheat option:
COD Noir: 2 Intel pieces. Turns graphics black and white.
Photo-Negative: 4 Intel pieces. Inverts the colors.
Super Contrast: 6 Intel pieces. Increases the contrast.
Ragtime Warfare: 8 Intel pieces. Silent Movie mode; graphics are black and white, dust and scratches fill the screen, game plays at two times the speed, and the music becomes piano music.
Cluster Bombs: 10 Intel pieces. Frag grenades are more powerful.
A Bad Year: 15 Intel pieces. Enemies explode into tires when shot.
Slow-Mo Ability: 20 Intel pieces. Slow motion game play.
Infinite Ammo: 30 Intel pieces.
# Mile High Club mission
Successfully complete Story mode on any difficulty, and watch the entire credits to unlock the Mile High Club mission.
# Prestige mode
Reach level 55 to unlock Prestige mode. This is a multiplayer only mode that starts you back at level 1. You can repeat this ten more times.
# Golden weapons
Successfully complete the indicated task to unlock the corresponding golden weapon camouflage. Note: The golden version of the weapons does not boost any attributes and is just purely cosmetic.
Golden Ak-47: Successfully complete all Assault Rifle challenges.
Golden Desert Eagle: Reach level 55.
Golden Dragonuv: Successfully complete all Sniper challenges.
Golden M1014: Successfully complete all Shotgun challenges.
Golden M60: Successfully complete all LMG challenges.
Golden Mini-Uzi: Successfully complete all SMG challenges.
# Rank bonuses
Reach the indicated rank in Multiplayer mode to unlock the corresponding bonus:
Private
Level 1: All starting equipment
Level 2: Demolitions Class Weapon Class
Level 3: Sniper Class Weapon Class
Lance Corporal
Level 4: Create a Class
Level 5: Gun Challenges
Level 6: New playlists
Corporal
Level 7: M21 Sniper Rifle
Level 8: Last Stand Perk Class 3
Level 9: Boot Camp Challenges 1
Sergeant
Level 10: M4 Carbine Assault Rifle
Level 11: UAV Jammer Perk Class 2
Level 12: Clan Tag
Staff Sergeant
Level 13: Mini Uzi Submachine Gun
Level 14: Bomb Squad Perk Class 1
Level 15: Boot Camp Challenges 2
Gunnery Sergeant
Level 16: M1911 Pistol
Level 17: Martyrdom Perk Class 2
Level 18: Boot Camp Challenges 3
Master Sergeant
Level 19: M60E4 Light Machine Gun
Level 20: Sleight of Hand Perk Class 2
Level 21: Operations Challenges
Master Gunnery Sergeant
Level 22: Dragunov Sniper Rifle
Level 23: Claymore Perk Class 1
Level 24: Operations Challenges 2
2nd Lieutenant
Level 25: G3 Assault Rifle
Level 26: Iron Lungs Perk Class 3
Level 27: Operations Challenges 3
1st Lieutenant
Level 28: AK-74U Submachine Gun
Level 29: Double Tab Perk Class 2
Level 30: Killer Challenges
Captain
Level 31: M1014 Shotgun
Level 32: Bandolier Perk Class 1
Level 33: Killer Challenges 2
Major
Level 34: R700 Sniper Rifle
Level 35: Eavesdrop Perk Class 3
Level 36: Killer Challenges 3
Lieutenant Colonel
Level 37: G36C Assault Rifle
Level 38: Overkill Perk Class 2
Level 39: Killer Challenges 4
Colonel
Level 40: P90 Submachine Gun
Level 41: Frag x3 Perk Class 1
Level 42: Humiliation Challenges
Brigadier General
Level 43: Desert Eagle Pistol
Level 44: Dead Silence Perk Class 3
Level 45: Humiliation Challenges 2
Major General
Level 46: M14 Assault Rifle
Level 47: Humiliation Challenges 3
Level 48: Humiliation Challenges 4
Lieutenant General
Level 49: Barret Sniper Rifle
Level 50: Humiliation Challenges 5
Level 51: Elite Challenges
Commander
Level 52: MP44 Assault Rifle
Level 53: Elite Challenges 2
Level 54: Elite Challenges 3
Level 55: Commander Prestige Mode and Golden Desert Eagle
# Intel locations
The Intel pieces can be found in the following missions. There are a total of thirty Intel pieces.
Mission 2: 2 Intel pieces
Mission 4: 2 Intel pieces
Mission 5: 3 Intel pieces
Mission 6: 2 Intel pieces
Mission 7: 2 Intel pieces
Mission 9: 3 Intel pieces
Mission 10: 2 Intel pieces
Mission 12: 2 Intel pieces
Mission 13: 3 Intel pieces
Mission 14: 2 Intel pieces
Mission 16: 2 Intel pieces
Mission 17: 1 Intel pieces
Mission 18: 2 Intel pieces
Mission 19: 2 Intel pieces
Prologue
Act 1
Act 2
Act 3
# Easy Intel pieces in "All Ghillied Up" mission
Go to the location of the first Intel Piece, located at the top of the ladder in the first church. Get the Intel Piece, and fall back down. You will die and start out getting the Intel Piece again. The Intel Piece keeps adding to the total number that you have. Repeat this process until you have 30 Intel Pieces.
# Easy experience
To level up faster than usual, try to use the same gun until all the marksman and elite challenges are completed. They provide huge boosts and will quickly level you up to get new guns. However, do not use those guns yet; just keep on the challenge until it has completed. The third phase of the challenge usually ends with 1,000 experience points, which usually increases you a rank in itself. Also, do not forget about the strange challenges like jumping 15 feet and surviving or falling 30 feet to your death. To complete the fall 30 feet to your death challenge if not previously unlocked, play the "Countdown" map, and jump into one of the open missile silos. You will get instant experience points for simply dying. Also, remember to go prone and crouch to get those challenges as well.
To level up, gain points, and complete challenges easily, find a TDM game on the "Shipment" map, preferably with a lot of people. Make sure you have the Steady Aim/Martyrdom/Stopping Power Perks enabled, and choose a gun you want to level up. Shipment is a very small close shoulder-to-shoulder map. Just run around holding down the trigger, taking down as many people as possible. This is very fast paced, and you should get points very quickly.
Play games such as Sabotage and Ground War to get lots of experience points because both games offer many kills. Sabotage has a long clock, giving you the opportunity to get many kills or challenges. Also, look for Sabotage on the "Wetworks" map. That map takes a lot of time up.
# Better accuracy
Once you get the Red Dot Scope add-on to your weapons, use it over the ACOG scope. The red dot will not enhance or take away anything and provides a better aim point on most weapons. The ACOG scope will actually add more range to your weapon, but take away accuracy which accomplishes almost nothing, especially for snipers because it takes away range and adds nothing.
# Better sniping
If a target is moving, make sure to lead it. If you are not making shots, try to lead your target more. Also, if you are a skilled sniper, try using the M40A3 over the M21. It has a slower reload time and rate of fire, but it has enough damage to kill a target in one shot instead of two or three. It also allows you to be less noticeable with less rounds being fired so someone else cannot follow the tracer shot back to you. A good setup for the sniper is the Claymore Perk to alert you when an enemy is trying to close in on your rear, and either the Sleight Of Hand or Stopping Power, then Iron Lungs to give you more time to line up your shots.
# "No Fighting In The War Room" mission checkpoints
Reach the listed location in the "No Fighting In The War Room" mission with at least the indicated amount of time left to get a checkpoint:
Checkpoint 1: The corner after the dining area/kitchen with 8 minutes 15 seconds
Checkpoint 2: Half way down the stairs with 7 minutes 45 seconds
Checkpoint 3: After the large area of creates and before the small corridor with 6 minutes 15 seconds
Checkpoint 4: Before the slow opening door with 3 minutes 30 seconds
Checkpoint 5: Just before you blow up the wall to the war room with 1 minute 15 seconds
# Extra ammunition for R700 sniper in Multiplayer mode
At level 38 in Multiplayer mode, you get the Overkill Perk Class 2 (located in the Perk 2 or Red Perks). This allows you to carry two primary weapons rather than a pistol. Some of the guns in online play can share ammunition. If you are a skilled sniper and prefer the bolt action to a semi-auto sniper, you can share ammo between the R700 (unlocked at level 34) and the G3 assault rifle (unlocked at level 25). Instead of having 40 rounds, you will have 152 rounds for the sniper, effectively giving you an endless supply of ammo for the R700. If you are a G3 user, you will gain an extra 40 rounds (two clips). This works both ways; since you share ammunition, you might not want to use too much ammo with the G3. Also, there are more combinations than just this one; experiment with different guns to see which ones can share ammo.
When you reach level 46, you will get the M14 Assault Rifle. In the class that you want to have the extra ammunition, you will need the M14 Assault Rifle and M21 Sniper Rifle as weapons. To use those two weapons, you must have Overkill (obtained at level 38) and your second Perk on Overkill. For the other two Perks, you can have whatever desired.
# Good sniping location in Crossfire map in Multiplayer mode
This spot can only be reached when you are playing the old school free-for-all section. Go to the building at the very end of the map on the opposite side of the bus. You can get to the very top of the building that is around the corner. First, get to the second story where the chair is found. Get on the top of the chair facing the wall, and jump. You may have to run and jump, but eventually you will catch an edge. You can then work your way up to a great sniping position.
# Dog attack in "All Ghillied Up" mission
In the "All Ghillied Up" mission, you will come across a wild dog eating a dead soldier's remains. You will be told to leave it alone, but if you want a very difficult challenge in the game, shoot it. You will be attacked by a large pack of angry dogs.
