Complete the following achievements to unlock Xbox Live Gamerscore points.

Successfully complete the game. A "Cheat" option will now appear during game play at the "Options" menu.

Collect the Intel Pieces (enemy laptop computers) hidden throughout the game to unlock the cheat options. The number of pieces you have determines which specific cheats are available.

The Intel Pieces can be found in the following levels. There are a total of thirty Intel Pieces.

Level 2: 2 Intel Pieces
Level 4: 2 Intel Pieces
Level 5: 3 Intel Pieces
Level 6: 2 Intel Pieces
Level 7: 2 Intel Pieces
Level 9: 3 Intel Pieces
Level 10: 2 Intel Pieces
Level 12: 2 Intel Pieces
Level 13: 3 Intel Pieces
Level 14: 2 Intel Pieces
Level 16: 2 Intel Pieces
Level 17: 1 Intel Piece
Level 18: 2 Intel Pieces
Level 19: 2 Intel Pieces

Successfully complete the game.

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

Successfully complete the game and watch the entire credits to unlock the bonus Epilogue mission.

Complete Story mode under any difficulty setting.

Golden weapons are a special camo that you get when you fully complete their respective weapon challenges.You can access them by choosing the camo of the respective weapon.The weapons don't get a boost or anything alike,it's purely cosmetic.

Each weapon is unlocked in multiplayer at a certain rank.

PROLOGUE: CREW EXPENDABLE~~~ 2 Intel

1 - The first intel is located after your rope down onto the deck, where you and your team kill several enemies, enter this area and walk down stairs where you will come to a drunk man. To the right of him is an alcove, enter here where you will find two men are sleeping, and next to your first intel.

2 - The second intel is located after helicopter support is given, and you clear out a hallway of enemies. You will go downstairs where you will find an open heating vent, with the second intel on top of it.

ACT 1: BLACKOUT~~~ 2 Intel

3 - After the start of the mission, you will come to a group of small houses. Inside one of these houses, you will find 2 terroristss and the first intel on Blackout.

4 - In the house holding Nikolai, on the second floor, you will find a bathroom with the intel on top of the toilet.

ACT 1: CHARLIE DON'T SURF~~~ 3 Intel

5 - In the basement of the first house your siege, you will find a smaller room off to the left, as you come down the stairs.

6 - After some fighting, you will come to an area where you need to cross the road in order to continue. This is also where you are charged by a truck. But, when you cross this road, you'll find a group of enemies sniping at you from an above floor. Kill them, and cross the street into the right, then go up the stairs, and you'll find an intel.

7 - Head down the road to where you find the general area where the truck is crashed. You'll find a second room in the corner and after going into it's second floor, you'll find the last intel.

ACT 1: THE BOG~~~ 2 Intel

8 - After finally getting through the group of enemies in nightvision, you'll come to where Royciwiz is attacked, for a seperate achievement, kill his attacker quickly. But, go up to where you were instructed, only to go back down. You'll find that a secondary group breached a door that isn't really important, but for you it is. go through it and look around to find the first intel on this level.

9 - After destroying the enemy tanks with the Javelin, you and your team will progress into a marketplace through a cut fence. Proceed until you find an upright fridge to your left, and just next to it will be the second intel.

ACT 1: THE HUNTED~~~ 2 Intel

10 - The area where you first encounter dogs, you might want to discover it first, then restart the checkpoint. Anyways, this area contains a building with a soda machine. In this building the intel will be on a table.

11 - After venturing through 2 greenhouses, you will come to an area where to your left is a wrecked building and in front of you a few enemies. Go through the wrecked building and under a small, tarp-covered area with the second intel.

ACT 1: WAR PIG~~~ 3 Intel

12 - After the your tank runs over the car, you will be on a corner street with a building to the left. Enter the building and go to the second floor. Find the first intel in a room here.

13 - Just across from this building, on the corner, you will find the next building on a dresser.

14 - All the way down the street, in the building right in front of you, you will find the 3rd intel on the second floor.

ACT 1: SHOCK AND AWE~~~ 2 Intel

15 - You will find the first intel in a corner on the second floor where you meet the recon team.

*Achievement Unlocked - Look Sharp - 20G*

16 - After hopping down from the building inhabiting the recon team, straight ahead is another building holding a few enemies. Clear it out and enter to find the next intel in a closet on the second floor.

ACT 2: SAFEHOUSE~~~ 2 Intel

17 - After clearing the forest and making your way up the hill to find a church to your left and a house with a sattelite dish attached to it. Make way to that house. You will find the intel on the second floor.

18 - You'll find it next to the water tower in a restaurant-like booth.

ACT 2: ALL GHILLIED UP~~~ 3 Intel

19 - When MacMillan states that there is a watch in the church, kill him and quickly climb up there after disposing of any more threats. Take the intel there and climb back down.

20 - Midway through the maze of cargo containers, you'll find a small group of terrorists huddled around a few barrels, kill them and take the intel that is on top of one of these barrels.

21 - After sneaking through the huge amount of enemies, MacMillan will acknowledge a sniper ontop of the fire escape in front of you. Take him out, and climb up the fire escape to meet a small room with the intel in it.

ACT 2: ONE SHOT, ONE KILL~~~ 2 Intel

22 - After taking out the helicopter, you need to carry MacMillan the rest of the way. You will come across a few enemies, and venture through a few buildings. After you make contact with the ground once more, you'll find a ladder next to you. Put MacMillan down and climb the ladder a few flights to find the intel.

23 - You'll come to an area where you need to put MacMillan down to ready yourself for an army of enemies. This one is tricky, but with the help of this guide, you'll be fine. Make sure as you climb out of the pool area, you find a corner secluding itself off to the left. Hold of the hord of enemies until the enemy helicopters come. Take the area I mentioned instead of the shorter way, (hopping over the white picket fence), and you will find a newly opened door. At the end of this hallway you will find the intel.

ACT 2: SINS OF THE FATHER~~~ 2 Intel

24 - After securing the area you begin at, make your way across the street into a diner. Quickly find the intel in a booth before the cinematic begins.

25 - You will chase after Zakhaev's son, who flees into a village. You will be told to take an alleyway where you will find a green car to your left and a red dumpster to your right. Take the right, and you will fight off a few terrorists. You will see a flight of metal stairs that lead to a small room. Kill the people guarding this room and take the intel.

ACT 3: ULTIMATUM~~~ 1 Intel

26 - After destroying the power tower with C4, you'll breach into an enemy base where you need to make your way to the right wall, and hug it until you come in to garage. Make your way to the back room and find the intel.

ACT 3: ALL IN~~~ 2 Intel

27 - After destroying the first BMP and making your way to the silo gate, backtrack until you find an alleyway leading behind a building, grab the intel here.

28 - After making your way through the silo gate, you will see the multiplayer map, "Countdown," but to your right you will see 3 silo hangars. Scout out the last one and find the intel in it.

ACT 3: NFITWR~~~ 2 Intel

29 - Follow Captain Price through the starting vents, and through a blood-stained bathroom to find you're given the option to take a left or right. Make your way left to find a darkened hallway with several rooms inhabiting it. Search through all the rooms to find a meeting room. Activate night vision and make your way around the table to find the intel.

30 - Once you breach the wall with the C4, go straight ahead and up the main stairs to your left. Make your way right and follow the small hallway to find a little meeting room with a map on the wall. Take the last intel.

*Achievement Unlocked - Eyes & Ears - 20G*

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.

Once you get the Red Dot Scope addon to your weapons, use it over the ACOG scope. The red dot will not enhance or take away anything and provides a better aimpoint on most weapons. The ACOG scope will actually add more range to your weapon, but take away accuracy which accomplishes almost nothing; especially so for snipers because it takes away range and adds nothing.

To level up quicker 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 and that will bump you up a rank almost in itself. Also, do not forget about the strange challenges like jumping 15 feet and surviving or falling 30 feet to your death. To get that one 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.

Never ever use the ACOG it is completely useless and hard to use stick with the red dot sight for a clearer easier to use view.

In any level or map in the middle of a battle crawl very slowly people may mistake you for a dead body.

1. Church tower
2. Where you see the guard on the emergency exit catwalk, shoot him and work your way to the top floor.

The multiplayer map overgrown is a tough map for some ppl but heres a way of seeing almost the entire map and get some kills while your at it. First go in front of the barn and go into the shack right next to it then go out the otherside of the shack and there should be a trash bin next to a rail, jump on the trash bin and then climb on top of the rail(warning you are very exposed doing this so do it fast!!)run across the rail until you get to the edge of the house and then jump onto the house and lie down on the roof, for this is a hard spot for ppl to see and very easy for you to see them and get kills.

In Act 2 in the sniper mission. "all ghilled up" there is a cool thing that happens. When MacMillian says you are nearly there you see a dog and he tell you to walk around it, but if you kill the dog then tons of dogs spawn and they will come after you.

When you spawn on the marines side you go to the builing in the middle of this side and go up the stairs and jump the small wall and you come out on to this extra bit on the roof with a metal roof and you walk a bit foward and jump to your left and you are now on a shed type thing and go prone and you bhave a good spot.

Go to the mission aftermath and do it on verern and all you have to do is walk around.

When you play on xbox live go and you want to get a gold gun fast then go into a cage match and ask the person that you are playing against to do headshots and then you will get a gold gun in no time.

When your playing veteran for gamerscore don't use cheats cos if you do then you don't get the achievment and it is quite frustrating.

If you have a mod you wanna read this, they put a mod block in right so all you have to do is put double tap on your gun,it wont work all the time but about 85% of the time it does.

This is pretty good for online play. When in a game lie down on the ground, sounds easy enough...then when lying on the ground, rappidly (DONT STOP) keep tapping Y when you do this it will keep swapping weapons.....But to all your friends, i will look like ur dead, if u want to see what it look likes tell your friends and let them try! NOW GO OUT THERE A FOOL SOME SOLDIERS! Happy Glitching! :-D

On xbox live if you unlock the Acog Scope for the m40a3 then even if you shoot someone in the toe it will kill them cos of the damage boost that the acog gives the gun.