Call of Duty: Modern Warfare 2/Contingency

Objectives

 * Follow Captain Price.
 * Keep enemies away from the submarine.

Walkthrough
Follow Captain Price closely and stay with him. Eventually you will come up to two men smoking, kill one of them when you are told to then continue forward. Kill the dog and his handler when you are told then continue forward with Captain Price. Run through the trees with him, stay crouching round the right side of the area and you won't be spotted. After you pass the search party, kill the three enemies on the left when you are told and pick up the intelligence on the crate under the parachute. You can kill the next patrol or sneak around it. You should kill the patrol after that though, line up the dog and the enemy and get a doublekill. Swap your pistol for an AK-47 then go to kill the final patrol, wait until you can get a doublekill then do this and kill the remaining troops. After this, you can rush to the top of the hill and slide down to meet up with Ghost. Hide behind the building and use the Predator Missile to get some kills, then use the AK-47 to kill any enemies that you see, after you feel you are safe, rush to the next building on the left, hide behind the window on the roof and kill enemies and use the Predator Missile until they are all dead.

Continue on to the submarine base, if you don't have one already, pick up a gun with a Grenade Launcher, then pick up the Light Machine-gun near the fence. There will be a hole in the wooden fence down the hill, slide down until you have a good shot at the enemy patrol with the grenade launcher and your team should move into position. Shoot the grenade launcher then use the predator missile on the Helicopter, move right and go through the door in the fence, lie down behind cover and wait for the game to save, then use the Predator missile again, a truck may come which would be a very good target, otherwise destroy some of the large gas tanks or aim towards a large group of enemies. Continue towards the submarine using the crates as cover, if you are running out of time, sprint to the objective point then once you get close enough for the objective to change, rush back to cover.

Now go up to the top of the building and snipe using the Dragunov, most of the enemies can easily be killed if you only use the predator missile on the vehicles as they come, you should only have to destroy three vehicles and two will come at a time, aim between them and you will destroy both of them. Hide behind the box as cover when you use the predator missile and snipe any enemies that get away. After the submarine's missile doors open, the mission will end.

Intelligence

 * When you have the chance to kill or leave the first patrol, look to your left and there will be a box under a parachute with intelligence on it.
 * After alerting the sub base, after the fence there will be a building on the left, inside there there will be some intelligence.
 * On the helicopter landing pad in a corner.