- 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.

- Easy 'New Squadron Record' achievement


- 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.

- Easy 'Three Of A Kind' achievement
After going down the stairs at the very beginning of the 'Crew Expendable' mission, knife the drunk soldier, then go into the room on right, and knife the two sleeping soldiers in the bed to get the 'Three Of A Kind' achievement.




- Golden weapons
Successfully complete the indicated task to unlock the corresponding golden weapon camouflage. Notice: The golden version of the weapons does not boost any attributes and is just purely cosmetic.

Golden Dragonuv	Successfully complete all Sniper challenges.
Golden M1014	Successfully complete all Shotgun challenges.
Golden Ak-47	Successfully complete all Assault Rifle challenges.
Golden Desert Eagle	Reach level 55.
Golden M60	Successfully complete all LMG challenges.
Golden Mini-Uzi	Successfully complete all SMG challenges.

- Cheat options
Acquire the indicated number of Intel pieces (enemy laptop computers) hidden throughout the game to unlock the corresponding cheat option:


- Rank bonuses
Reach the indicated rank in Multiplayer mode to unlock the corresponding bonus:


Private

Level 1	All begining 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

- 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.

- Easy 'Your Show Sucks' achievement


- Completion bonuses
Successfully 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.

- '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 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 1	The corner after the dining area/kitchen with 8 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

- Easy 'Bird On The Ground' achievement


- Intel locations
The Intel pieces can be found in the following missions. There are a total of thirty Intel pieces.

Mission 7	2 Intel pieces
Mission 14	2 Intel pieces
Mission 16	2 Intel pieces
Mission 9	3 Intel pieces
Mission 17	1 Intel pieces
Mission 4	2 Intel pieces
Mission 12	2 Intel pieces
Mission 5	3 Intel pieces
Mission 2	2 Intel pieces
Mission 10	2 Intel pieces
Mission 13	3 Intel pieces
Mission 18	2 Intel pieces
Mission 6	2 Intel pieces
Mission 19	2 Intel pieces

Prologue





Act 1





Act 2





Act 3




- Prestige mode
Reach level 55 to unlock Prestige mode. This is a multiplayer only mode that begins you back at level 1. You can repeat this ten more times.

- 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.

- Mile High Club mission
Successfully complete Story mode on any difficulty, and watch the entire credits to unlock the Mile High Club mission.

- Easy 'Mile High Club' achievement


- Achievements
Do the following things to obtain the corresponding Gamerscore points. Notice: Enabling cheats will prevent achievements from being earned.

10 Points
Daredevil	Kill an enemy while blinded by a flashbang in the single player campaign.
Roadkill	Kill 2 enemies by blowing up a car in the single player campaign.
No Rest for the Weary	Stab an injured crawling enemy.
Man of the People	Save the farmer.
Three of a Kind	Kill 3 enemies sequentially with your knife in the single player campaign.
20 Points
Piggyback Ride	Carry Cpt. MacMillian to safety.
Wrong Number	Find Al-Asad's safehouse.
Ghillies In The Mist	Finish 'All Ghillied Up' without alerting any enemies.
Rescue Roycewicz	Save Pvt. Roycewicz on the stairs.
Your Show Sucks	Destroy all the TVs showing Al-Asad's speech.
Look Sharp	Find 15 enemy intel items.
Bird on the Ground	Shoot down an enemy helicopter with an RPG in the single player campaign.
Make the Jump	Infiltrate a cargo ship.
Desperate Measures	Corner Zakhaev's Son.
Mile High Club	Sky dive to safety on Veteran difficulty.
Dancing in the Dark	Kill the power.
Gain a Be victorious inged Dagger	Finish 'F.N.G.'.
Death From Above	Operate an AC-130 gun ship.
Straight Flush	Kill 5 enemies with one shot while in the AC-130 gunship.
Eyes and Ears	Find 30 enemy intel items.
New Squadron Record	Finish the cargo ship mockup in less than 20 seconds.
Save the Bacon	Protect 'War Pig', the Abrams tank.
Four of a Kind	Kill 4 enemies sequentially with headshots in the single player campaign.
Down Boy Down	Survive a dog attack.
40 Points
The Bog	Finish 'The Bog' and 'War Pig' on Veteran difficulty.
Be victorious in the War	Finish the game on any difficulty.
The First Horseman	Finish 'Shock and Awe' on Veteran difficulty.
The Second Horseman	Finish 'Safehouse' on Veteran difficulty.
The Escape	Finish 'Hunted' and 'Death From Above' on Veteran difficulty.
The Ultimatum	Finish 'Ultimatum', 'All In', and 'No Fighting in the War Room' on Veteran difficulty.
The Package	Finish 'Crew Expendable' on Veteran difficulty.
The Shot	Finish 'All Ghillied Up' and 'One Shot, One Kill' on Veteran difficulty.
The Fourth Horseman	Finish 'Game Over' on Veteran difficulty.
The Third Horseman	Finish 'Heat' and 'The Sins of the Father' on Veteran difficulty.
The Rescue	Finish 'Blackout' on Veteran difficulty.
The Search	Finish 'Charlie Don't Surf' on Veteran difficulty.
90 Points
Deep and Hard	Finish the game on Hardened or Veteran difficulty.

- 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 activated, and choose a gun you want to level up. Shipment is a very small close shoulder-to-shoulder map. Just run around keep pusheding 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 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.