This is my complete guide to the Special Ops missions on Modern Warfare 3. I hope you enjoy reading this thread, and I hope it helps you out a lot!
It took me a long time to write and get correct details, but not all of them may be correct, and I am sorry in advance for that.
Enjoy!

Stay Sharp
This mission is similar to the training camp missions that began previous Modern Warfare games. You do not select a difficulty, but instead, your star ranking depends on your speed and performance. For three stars, you must complete the course within 28 seconds, shooting every enemy target but none of the civilian targets. You'll probably need to learn the course by muscle memory, but here are a few tips to help you shave precious seconds off your time.
First off, I suggest using two pisols: the starting USP .45 and the P99. Equip the USP first, so you can use its faster knife attack. Here's another tip: tap the left trigger to snap to targets instead of manually aiming, if you can help it. Finally, a third tip: save time by hipfiring at nearby targets while moving. They're bigger than actually human enemies, so this is much more effective here than in the rest of the game.
For the first wave, shoot the guards on the left and right. For the next, shoot the front target as well as those those on the left and right while leaving the civilian in the green dress unharmed. On the following building, take out the targets in the windows and on the left and right of the balcony, but spare the man in the suit and the woman in a pink dress.
In the next hallway, melee the target with your knife. On the second floor, shoot the two enemies on the left (with one bullet if you can), then the one on the right, leaving the woman unharmed. Change to your other pistol as you advance.
Shoot the fearsomely realistic dogs with hipfire. Aim and shoot the master as well, then shoot the two above and to the right, as well as the one above the doorway, allowing you to pass through it. Finally, enter and take out all four targets with hipfire while sparing the very real man in the middle of them.

Milehigh Jack
In these missions, you'll have to select your difficulty at the beginning, which will determine how many starts you receive when you win. Pick a difficulty you feel comfortable with. The same basic strategy works on regular as well as veteran, but obviously you'll have to fight much more carefully and make better use of cover for the latter. The difficulty affects not only the combat, but the time limit as well. Your time for Regular is 3:30, but for Veteran, it's just 1:50.
The mission starts with a breach, so take out all four guards during the slow-motion sequence. There are two more around the corner, so keep your distance and shoot them. Fight your way through several enemies in the next area to reach the stairs leading up, but watch out for the guy in the compartment behind the stairs. You should take these stairs, if that wasn't evident already.
At the top of the stairs, a few more guys will rush you in the hallway. Bring them down, then round the corner to be caught by surprise by another enemy jumping around the corner. Take him down too, as well as his buddy behind him.
Breach the door and shoot the four guards in the room, being careful not to miss the one coming to a stand in the far corner. After the breach, two more enemies will enter through the door with a flashbang, so duck behind the doorway for cover. After the flash, take both of them out and interact with the President to complete the mission.

Over Reactor
When you land on the sub, shoot the enemies coming out of the smoke on the left and the right, then disable the thermite charge, which will start the reactor countdown. To stop it, drop down and head through the only door into a series of catacombs. Press RIGHT to switch to thermal vision if you want, then take out the four enemies on the upper level and the three enemies on the lower level. Don't neglect the shotgun in your secondary weapon slot.
Head out through the exit on the lower level and shoot the guard coming through it. Shoot the gunman up top, then eliminate the two down below. Three more will approach from all sides as you turn left, another good time to use that shotgun of yours. Turn right here to reach the red reaction room.
Immediately stab a melee-attacking guard on your left. Head down the left path and shoot three guards standing in a row. Around the corner to the right are three more guards. Follow that path to a boiler room with a valve for you to turn. If you've got a partner, have him watch your back while you do this; otherwise, stop midway to fend off the attackers before finishing the job.
It isn't over yet. Head around the right path and eliminate the guards if you didn't already kill them, then continue for a few more enemies and then a ladder. Climb the ladder to reach the top, then run to the other side of the sub. Shoot the guards that attack at the halfway point, then continue running to the objective, with more guards to shoot. Now simply wait for your evac helicopter and then approach it.

Hit and Run
Collect whatever weapons you want, but I personally like the starting setup. Drop down to prompt the first enemy wave to attack. Immediately head for the target building, fight through the few enemies on the stairs, and kill the first target at the top of the stairs.
For the secon target, head outside and run to the target's building, then head through the door next to the stairs instead of taking the stairs. Shoot the enemies inside, and the target should be among them. This completes the first half of the mission, but there are still hostages to save.
Head out the door toward the hostages and walk along the bridge to the adjacent roof. Where the path on that roof ends, drop down and continue running toward the crate with the hostages. Take shelter here and free the hostages, then throw a smoke grenade to call in an evac helicopter. Fight off the enemies from this crate for a spell. A big army will show up just before you escape, so stall them with your remaining grenades and flashbangs. When the helicopter arrives, your mission is done.

Toxic Paradise
You get to wear a juggernaut suit in this mission. Head through the alley shoot the enemies with your machine gun. When you reach the central area, you may want to use the grenade launcher to clear groups on enemies. In the lower area ahead, throw an air support marker in there. Collect the samples on the left and right of the area before continuing, using the canisters for cover as you do so.
As you advance, watch out for enemy air support attacks. Head down into the lower area ahead, then ascend the stairs on the left while shooting the descending enemies. Hit the jeep ahead with air support to take it out. Take a ladder to go through a house with more enemies, then exit to reach the third canister and take a sample. There's also an enemy with a riot shield, which you can take to make yourself nearly unstoppable.
Head downstairs into the street to engage more enemy forces. These guys will be throwing air support and regular grenades left and right, so don't get cocky. Your reward for beating them is an ammo box, which will refill even your starting grenade launcher to maximum capacity. There's also a fourth canister here.
Proceed through a building full of enemies (a good time to make use of that grenade launcher), use the second ammo box in the kitchen and head out into the alley, where a Juggernaut awaits, with the same armoring as you. Unfortunately for him, you have a full grenade launcher and he has no grenade launcher. A few grenades from a distance should take him down. If you don't have a grenade launcher, you should be able to find an RPG nearby, or you can try using air support. He's always on the move, so place the air support where you think he will be when the actual air support arrives.
In the next building, you'll be blocked by a bar. Unfortunately, Juggernauts can't jump. Instead, head upstairs and grab the other chemical sample first. Afterward, shoot the enemies below, and once they thin out, take the stairs down and grab the last sample. When all the sample are collected, head toward the objective. Kill a few more enemies, and then head up to the roof to be extracted.

Firewall
This is a Co-Op Only Mission. One player will be a soldier on the ground while the other controls a sentry turret. Additionally, there is a time limit to complete the mission.
At the beginnign, the turret should focus on clearing out the area he can see while the soldier runs through the building with the shotgun. With the turret covering you, run out as the soldier and use the laptop to advance the turret player to a turret in a new room. Immediately, the turret player should start shooting the enemies coming out of here.
When the room is clear, the soldier player should run up the stairs, at which point the turret player should switch over to the outside view of the building and shoot the enemies ahead of the soldier. The soldier can then work his way up the stairs and use another computer.
The turret player will now have access to a new turret in the dock yard. Use the turret to shoot down a couple of helicopters. The soldier can then cross the yard while the turret covers him. When the soldier reaches the building, have the turret camera switch to the gate area. Here, shoot the numerous enemies with the turret, allowing the soldier to reach the next laptop.
The turret will now be in the parkway. As the soldier comes in (from the right), turn left and take out the enemies. Now switch the turret to the construction yard and take out these enemies as the soldier advances to this area. While you're at it, take out any helicopters with the turret too. Now cover the soldier while he heads to the extraction point.

Fatal Extraction
Swap your pistol for a shotgun or rifle, then head outside. Snipe the four enemies on the roof to the right. Now take out the enemies in the central stalls, including a couple of hyenas that run toward you. Take out the enemies on the right and the turret as well, then take cover in that building. Continue to pick off enemies, and you'll find that certain random ones are dropping intel. Defeat the enemies and collect all the locally available intelligence, then advance to the indicated safehouse.
Outside, take out a turret on the left and enemies on the right. Proceed down the road, taking cover in various buildings, to advance. Shoot the turret on the roof ahead. Further ahead, fight more enemies, including two hyenas and a turret on your right. When you've collected all the intel here, take out a turret covering the marked path, then continue and crouch to enter a sewer pipe. As you go through, one enemy will shoot you from ahead. Take him out.
On the other side of the pipe, run to a ladder and climb up to escape a pursuing hyena. Hold your position for a minute, then press RIGHT to switch to the laser painter. Aim at the enemy safehouse until it beeps, then pull the right trigger to initiate an air strike. This will end the mission.

Hostage Taker
Snake, this is a sneaking mission. When you get up, you will be surrounded by enemies. Shoot them from afar, stab them, or avoid them entirely. Up ahead are some enemies about to execute a hostage; shoot them, but don't get caught in the helicopter's searchlight. When the helicopter leaves, free the hostage and go through the broken fence.
Head forward and take out the enemy ahead, then shoot the next guy before he can execute the second hostage. Free the hostage and kill the next two, then head to the objective after letting the helicopter pass again. All the enemies ahead can be eliminating with some stealthy stabbing, allowing you to proceed and jump over a log.
Shoot the next few enemies and free the last hostage, then avoid the helicopter and head to Elena's position. There will be a slow-mo breach-like sequence in which you must shoot Elena's captors but not Elena herself. This is a tricky shot; aim for the captor's head to avoid hitting Elena. Once Elena is safe, the misson's over.

Charges Set
It's round two of the obstacle course. This time, I recommend the Five-Seven as your first pistol and the USP .45 as your second. To begin place a charge on the door to breach it.
Shoot the four enemy targets inside from right to left, but don't shoot the girls in pink. Head out the door on your left, and shoot the two guards and the approaching dog from left to right, hipfiring at the dog as you approach. When you come to the gate shoot the left target, then the sniper above, then the two on the right.
Time for another breach. In here, shoot the guards from right to left, and don't miss the one in the shadow on the far left. Avoid hitting the civilian girls in bright colors, obviously. Switch to your USP and sprint down the stairs, stab the target, and sprint some more. Shoot the three enemies from left to right, but not the businessman or the little girl.
Around the corner, shoot the enemy on the far left, then the two on the bridge, then the one on the right. Run a little further, shoot the guards on your immediate left and right, then sprint ahead to the finish line. Your goal for three stars is 33 seconds.
Resistance Movement
This mission focuses on stealth as well; going loud will likely mean the death of the rebels you're trying to save. Come out of the building and shoot the two guards on your left and right before they notice you. Snipe the two guards ahead to free their hostage. Ask him to come with you.
Snipe the next guard in the building on your right through a window, then enter the building and shoot the other guard. Behind the counter is another rebel to take with you. Despite what your map may say, there's no way through these buildings, so head back onto the street.
Progress a little further, and you'll hear a dog barking. Shoot the dog before it catches the rebel it's chasing, then kill the guards as well before they notice you. Take this rebel with you as well. Progress further and shoot two guards ahead, then two more on the left along with another dog. In an alcove at the end of the road is another rebel to collect. Turn to the parking lot on your left and take out two more guards, then enter the door.
Head up the stairs and turn around to snipe an enemy, then continue past him. Shoot the next two guards with your silenced pistol, then round the corner and stab the next guy on the left. Further on, shoot the guard at the door and stab the one sleeping in a chair, then head back downstairs.
Down the hall is another guard to shoot. Sneak out and wait for the two guards to pass, then shoot the two right in front of you. Once they're down, you can turn right and safely take out those two guards from before. Up ahead take out three guards holding a prisoner and rescue him, then continue and jump a fence.
There will be two guards coming down the street and one on the corner. Take them all down. Inside the building is another rebel, hiding. Take out the guard and the dog on the other side, then run to the extraction point.

Little Bros
You'll be under attack right from the start. Hold off the enemies until backup arrives in the form of a drop helicopter. Take out all the enemies nearby to allow the chopper to land. Jump on the helicopter to be moved to your real destination. During the flight, continue to cover the helicopter, especially with regard to any enemies with rockets.
Once you reach the roof, shoot the enemies and head inside. Fight your way down the stairs into the lower room. Here, the enemies will drop smoke. Fight through the smoke and drop down to the lower level through the hole in the floor.
Clear the bottom floor out, then head to the bomb in one of the central cubicles and arm it. Head through the hall and around the corner toward the extraction point, shooting the enemies as they come up the stairs. Run to the exfil point, and as you fly away, the building will explode.

Invisible Threat
It's another Juggernaut mission! This time, your job is to locate and clear out IEDs. To locate them, you'll need to press RIGHT to access your UAV, from which any IEDs you see will be marked. You can also launch Predator Missiles from the UAV.
Once the first few IEDs are marked, engage the enemies in the area to thin them out so they don't kill you while you disarm the IEDs. When the Predator becomes available again, use it to mark the next three IEDs, then fire a missile on the enemy position.
Back on the ground, make use of your full grenade launcher and wipe out the enemies standing between you and the next three IEDs. Disarm them once the area is clear. When an enemy tank arrives, take it out with a Predator Missile, which will also reveal the next IEDs. Before you take out the last one, an enemy helicopter will arrive. You can either shoot down the helicopter with grenades or a missile, or if you have enough time, you can just finish disarming the IED and the mission will end shortly afterward.

Server Crash
This mission's pretty cool. As you ride the truck through the streets, you can shoot groups of enemies with your grenade launcher. You also have a rifle, with another grenade launcher on it! That's a lot of grenades. However, shortly after you start, you'll find out why you need them as trucks give chase to your vehicle. Turn around and take them out with grenades before they take you out.
After taking out several trucks in succession, you'll get a little break. Shoot the enemies ahead of the vehicle, then the truck. You'll come upon a couple more trucks ahead, and then you'll get out of the vehicle. You'll have to do the second part of the mission on foot.
Inside the building, you may wish to switch to the rifle because of the tight spaces. When you get down to the ladder, throw a flashbang down first, then drop into the sewers and fight more enemies. Once you get down into the computer room, clear the area and stick the transimitter to the computer.
You'll have to defend the area during the download, and enemies will come from both sides. Some will even have riot shields, though those will be very useful if you get your hands on them. The enemies will alternate coming from each entrance, so take them out quickly before they start to build up. When the download finishes, grab the box and head back up.
You'll have to face a Juggernaut in the sewers. Use your grenade launcher to bring him down. Fight through just a few more enemies to get back up top and hop in the jeep to exfiltrate.

Smack Down
You'll be shooting from a helicopter at first. Take out the truck that's following you, then clear out the enemies in the first area with the aid of your grenade launcher. Afterward, check the roof on the right for more enemies. When they're all down, the helicopter will move on.
Take out the few enemies on the balconies and rooftops, and use your grenade launcher to kill the cluster of enemies on one roof. Shoot the enemy firing rockets at you and his two buddies on the upper roof. Continue shooting enemies as the helicopter moves, and before it's time to get off, quickly shoot the approaching truck with a grenade.
Now you'll be forced to jump down and fight on foot. To reach the drug package on the right, head up through the first accessible building and take the ladder to the roof, then jump from roof to roof to reach the one with the drugs. Blow the drugs up from a safe distance with C4.
The enemies won't be happy about this and will call in reinforcements. Now head into the opposite building and simply take the stairs to the other drug package. Blow this one up too, and get out of there, heading for the helicopter. Take out a few more enemies and run to the helicopter to complete the mission.

Flood the Market
You start the mission with the XM25 grenade launcher in your back pocket. You'll need it too, because in the very first area, there are waves upon waves of enemy soldiers. When the enemies stop coming, head into the stock exchange building.
Refill your ammo at the ammo box, then use your XM25 take out the enemies on the main floor of the building. Take the first of the encryption codes inside, and another wave will invade from the stairs, so quickly turn around and take them out.
There are two more codes in here to collect while engaging waves of enemies. When all three are in your possession, head up to the roof to upload the data. Plant the transmitter, then engage the enemies shooting from the opposite building. Take them out from cover before they start using their gas grenades against you.
Shortly after starting the download, a wave of enemies will come from downstairs and make life a lot harder for you. Find somewhere to hole up until the download completes, because when it does, the mission will end automatically.

Fire Mission
This is the more annoying of the two co-op missions, but thankfully it's very brief. The premise is simple: the player on the ground must advance while the player in the air must shoot the scores of enemies attacking the advancing player.
The player in the air basically decides if the player on the ground lives or dies. First off, don't shoot him, obviously. Secondly, be sure to take out the enemies he's trying to advance through, as there's no need for him to have to even fight most of them. Just aim for the area ahead of your teammate and wipe it out, then switch to another weapon to avoid having to wait on the weapon's cooldown. If you see a truck or a helicopter, take it out quickly so your teammate doesn't get himself killed.
The player on the ground should be careful not to advance too quickly, or he'll be too close for the player in the sky to shoot the enemies. Simply keep your distancek, let your ally eliminate most of the enemies, and pick off the stragglers before continuing. When you reach the objective successfully, you'll realize just how short this mission actually was. Enough friendly fire accidents can make any mission seem long.

This is my complete guide to the Special Ops missions on Modern Warfare 3. I hope you enjoy reading this thread, and I hope it helps you out a lot!
It took me a long time to write and get correct details, but not all of them may be correct, and I am sorry in advance for that.
Enjoy!

Stay Sharp
This mission is similar to the training camp missions that began previous Modern Warfare games. You do not select a difficulty, but instead, your star ranking depends on your speed and performance. For three stars, you must complete the course within 28 seconds, shooting every enemy target but none of the civilian targets. You'll probably need to learn the course by muscle memory, but here are a few tips to help you shave precious seconds off your time.
First off, I suggest using two pisols: the starting USP .45 and the P99. Equip the USP first, so you can use its faster knife attack. Here's another tip: tap the left trigger to snap to targets instead of manually aiming, if you can help it. Finally, a third tip: save time by hipfiring at nearby targets while moving. They're bigger than actually human enemies, so this is much more effective here than in the rest of the game.
For the first wave, shoot the guards on the left and right. For the next, shoot the front target as well as those those on the left and right while leaving the civilian in the green dress unharmed. On the following building, take out the targets in the windows and on the left and right of the balcony, but spare the man in the suit and the woman in a pink dress.
In the next hallway, melee the target with your knife. On the second floor, shoot the two enemies on the left (with one bullet if you can), then the one on the right, leaving the woman unharmed. Change to your other pistol as you advance.
Shoot the fearsomely realistic dogs with hipfire. Aim and shoot the master as well, then shoot the two above and to the right, as well as the one above the doorway, allowing you to pass through it. Finally, enter and take out all four targets with hipfire while sparing the very real man in the middle of them.

Milehigh Jack
In these missions, you'll have to select your difficulty at the beginning, which will determine how many starts you receive when you win. Pick a difficulty you feel comfortable with. The same basic strategy works on regular as well as veteran, but obviously you'll have to fight much more carefully and make better use of cover for the latter. The difficulty affects not only the combat, but the time limit as well. Your time for Regular is 3:30, but for Veteran, it's just 1:50.
The mission starts with a breach, so take out all four guards during the slow-motion sequence. There are two more around the corner, so keep your distance and shoot them. Fight your way through several enemies in the next area to reach the stairs leading up, but watch out for the guy in the compartment behind the stairs. You should take these stairs, if that wasn't evident already.
At the top of the stairs, a few more guys will rush you in the hallway. Bring them down, then round the corner to be caught by surprise by another enemy jumping around the corner. Take him down too, as well as his buddy behind him.
Breach the door and shoot the four guards in the room, being careful not to miss the one coming to a stand in the far corner. After the breach, two more enemies will enter through the door with a flashbang, so duck behind the doorway for cover. After the flash, take both of them out and interact with the President to complete the mission.

Over Reactor
When you land on the sub, shoot the enemies coming out of the smoke on the left and the right, then disable the thermite charge, which will start the reactor countdown. To stop it, drop down and head through the only door into a series of catacombs. Press RIGHT to switch to thermal vision if you want, then take out the four enemies on the upper level and the three enemies on the lower level. Don't neglect the shotgun in your secondary weapon slot.
Head out through the exit on the lower level and shoot the guard coming through it. Shoot the gunman up top, then eliminate the two down below. Three more will approach from all sides as you turn left, another good time to use that shotgun of yours. Turn right here to reach the red reaction room.
Immediately stab a melee-attacking guard on your left. Head down the left path and shoot three guards standing in a row. Around the corner to the right are three more guards. Follow that path to a boiler room with a valve for you to turn. If you've got a partner, have him watch your back while you do this; otherwise, stop midway to fend off the attackers before finishing the job.
It isn't over yet. Head around the right path and eliminate the guards if you didn't already kill them, then continue for a few more enemies and then a ladder. Climb the ladder to reach the top, then run to the other side of the sub. Shoot the guards that attack at the halfway point, then continue running to the objective, with more guards to shoot. Now simply wait for your evac helicopter and then approach it.

Hit and Run
Collect whatever weapons you want, but I personally like the starting setup. Drop down to prompt the first enemy wave to attack. Immediately head for the target building, fight through the few enemies on the stairs, and kill the first target at the top of the stairs.
For the secon target, head outside and run to the target's building, then head through the door next to the stairs instead of taking the stairs. Shoot the enemies inside, and the target should be among them. This completes the first half of the mission, but there are still hostages to save.
Head out the door toward the hostages and walk along the bridge to the adjacent roof. Where the path on that roof ends, drop down and continue running toward the crate with the hostages. Take shelter here and free the hostages, then throw a smoke grenade to call in an evac helicopter. Fight off the enemies from this crate for a spell. A big army will show up just before you escape, so stall them with your remaining grenades and flashbangs. When the helicopter arrives, your mission is done.

Toxic Paradise
You get to wear a juggernaut suit in this mission. Head through the alley shoot the enemies with your machine gun. When you reach the central area, you may want to use the grenade launcher to clear groups on enemies. In the lower area ahead, throw an air support marker in there. Collect the samples on the left and right of the area before continuing, using the canisters for cover as you do so.
As you advance, watch out for enemy air support attacks. Head down into the lower area ahead, then ascend the stairs on the left while shooting the descending enemies. Hit the jeep ahead with air support to take it out. Take a ladder to go through a house with more enemies, then exit to reach the third canister and take a sample. There's also an enemy with a riot shield, which you can take to make yourself nearly unstoppable.
Head downstairs into the street to engage more enemy forces. These guys will be throwing air support and regular grenades left and right, so don't get cocky. Your reward for beating them is an ammo box, which will refill even your starting grenade launcher to maximum capacity. There's also a fourth canister here.
Proceed through a building full of enemies (a good time to make use of that grenade launcher), use the second ammo box in the kitchen and head out into the alley, where a Juggernaut awaits, with the same armoring as you. Unfortunately for him, you have a full grenade launcher and he has no grenade launcher. A few grenades from a distance should take him down. If you don't have a grenade launcher, you should be able to find an RPG nearby, or you can try using air support. He's always on the move, so place the air support where you think he will be when the actual air support arrives.
In the next building, you'll be blocked by a bar. Unfortunately, Juggernauts can't jump. Instead, head upstairs and grab the other chemical sample first. Afterward, shoot the enemies below, and once they thin out, take the stairs down and grab the last sample. When all the sample are collected, head toward the objective. Kill a few more enemies, and then head up to the roof to be extracted.

Firewall
This is a Co-Op Only Mission. One player will be a soldier on the ground while the other controls a sentry turret. Additionally, there is a time limit to complete the mission.
At the beginnign, the turret should focus on clearing out the area he can see while the soldier runs through the building with the shotgun. With the turret covering you, run out as the soldier and use the laptop to advance the turret player to a turret in a new room. Immediately, the turret player should start shooting the enemies coming out of here.
When the room is clear, the soldier player should run up the stairs, at which point the turret player should switch over to the outside view of the building and shoot the enemies ahead of the soldier. The soldier can then work his way up the stairs and use another computer.
The turret player will now have access to a new turret in the dock yard. Use the turret to shoot down a couple of helicopters. The soldier can then cross the yard while the turret covers him. When the soldier reaches the building, have the turret camera switch to the gate area. Here, shoot the numerous enemies with the turret, allowing the soldier to reach the next laptop.
The turret will now be in the parkway. As the soldier comes in (from the right), turn left and take out the enemies. Now switch the turret to the construction yard and take out these enemies as the soldier advances to this area. While you're at it, take out any helicopters with the turret too. Now cover the soldier while he heads to the extraction point.

Fatal Extraction
Swap your pistol for a shotgun or rifle, then head outside. Snipe the four enemies on the roof to the right. Now take out the enemies in the central stalls, including a couple of hyenas that run toward you. Take out the enemies on the right and the turret as well, then take cover in that building. Continue to pick off enemies, and you'll find that certain random ones are dropping intel. Defeat the enemies and collect all the locally available intelligence, then advance to the indicated safehouse.
Outside, take out a turret on the left and enemies on the right. Proceed down the road, taking cover in various buildings, to advance. Shoot the turret on the roof ahead. Further ahead, fight more enemies, including two hyenas and a turret on your right. When you've collected all the intel here, take out a turret covering the marked path, then continue and crouch to enter a sewer pipe. As you go through, one enemy will shoot you from ahead. Take him out.
On the other side of the pipe, run to a ladder and climb up to escape a pursuing hyena. Hold your position for a minute, then press RIGHT to switch to the laser painter. Aim at the enemy safehouse until it beeps, then pull the right trigger to initiate an air strike. This will end the mission.

Hostage Taker
Snake, this is a sneaking mission. When you get up, you will be surrounded by enemies. Shoot them from afar, stab them, or avoid them entirely. Up ahead are some enemies about to execute a hostage; shoot them, but don't get caught in the helicopter's searchlight. When the helicopter leaves, free the hostage and go through the broken fence.
Head forward and take out the enemy ahead, then shoot the next guy before he can execute the second hostage. Free the hostage and kill the next two, then head to the objective after letting the helicopter pass again. All the enemies ahead can be eliminating with some stealthy stabbing, allowing you to proceed and jump over a log.
Shoot the next few enemies and free the last hostage, then avoid the helicopter and head to Elena's position. There will be a slow-mo breach-like sequence in which you must shoot Elena's captors but not Elena herself. This is a tricky shot; aim for the captor's head to avoid hitting Elena. Once Elena is safe, the misson's over.

Charges Set
It's round two of the obstacle course. This time, I recommend the Five-Seven as your first pistol and the USP .45 as your second. To begin place a charge on the door to breach it.
Shoot the four enemy targets inside from right to left, but don't shoot the girls in pink. Head out the door on your left, and shoot the two guards and the approaching dog from left to right, hipfiring at the dog as you approach. When you come to the gate shoot the left target, then the sniper above, then the two on the right.
Time for another breach. In here, shoot the guards from right to left, and don't miss the one in the shadow on the far left. Avoid hitting the civilian girls in bright colors, obviously. Switch to your USP and sprint down the stairs, stab the target, and sprint some more. Shoot the three enemies from left to right, but not the businessman or the little girl.
Around the corner, shoot the enemy on the far left, then the two on the bridge, then the one on the right. Run a little further, shoot the guards on your immediate left and right, then sprint ahead to the finish line. Your goal for three stars is 33 seconds.
Resistance Movement
This mission focuses on stealth as well; going loud will likely mean the death of the rebels you're trying to save. Come out of the building and shoot the two guards on your left and right before they notice you. Snipe the two guards ahead to free their hostage. Ask him to come with you.
Snipe the next guard in the building on your right through a window, then enter the building and shoot the other guard. Behind the counter is another rebel to take with you. Despite what your map may say, there's no way through these buildings, so head back onto the street.
Progress a little further, and you'll hear a dog barking. Shoot the dog before it catches the rebel it's chasing, then kill the guards as well before they notice you. Take this rebel with you as well. Progress further and shoot two guards ahead, then two more on the left along with another dog. In an alcove at the end of the road is another rebel to collect. Turn to the parking lot on your left and take out two more guards, then enter the door.
Head up the stairs and turn around to snipe an enemy, then continue past him. Shoot the next two guards with your silenced pistol, then round the corner and stab the next guy on the left. Further on, shoot the guard at the door and stab the one sleeping in a chair, then head back downstairs.
Down the hall is another guard to shoot. Sneak out and wait for the two guards to pass, then shoot the two right in front of you. Once they're down, you can turn right and safely take out those two guards from before. Up ahead take out three guards holding a prisoner and rescue him, then continue and jump a fence.
There will be two guards coming down the street and one on the corner. Take them all down. Inside the building is another rebel, hiding. Take out the guard and the dog on the other side, then run to the extraction point.

Little Bros
You'll be under attack right from the start. Hold off the enemies until backup arrives in the form of a drop helicopter. Take out all the enemies nearby to allow the chopper to land. Jump on the helicopter to be moved to your real destination. During the flight, continue to cover the helicopter, especially with regard to any enemies with rockets.
Once you reach the roof, shoot the enemies and head inside. Fight your way down the stairs into the lower room. Here, the enemies will drop smoke. Fight through the smoke and drop down to the lower level through the hole in the floor.
Clear the bottom floor out, then head to the bomb in one of the central cubicles and arm it. Head through the hall and around the corner toward the extraction point, shooting the enemies as they come up the stairs. Run to the exfil point, and as you fly away, the building will explode.

Invisible Threat
It's another Juggernaut mission! This time, your job is to locate and clear out IEDs. To locate them, you'll need to press RIGHT to access your UAV, from which any IEDs you see will be marked. You can also launch Predator Missiles from the UAV.
Once the first few IEDs are marked, engage the enemies in the area to thin them out so they don't kill you while you disarm the IEDs. When the Predator becomes available again, use it to mark the next three IEDs, then fire a missile on the enemy position.
Back on the ground, make use of your full grenade launcher and wipe out the enemies standing between you and the next three IEDs. Disarm them once the area is clear. When an enemy tank arrives, take it out with a Predator Missile, which will also reveal the next IEDs. Before you take out the last one, an enemy helicopter will arrive. You can either shoot down the helicopter with grenades or a missile, or if you have enough time, you can just finish disarming the IED and the mission will end shortly afterward.

Server Crash
This mission's pretty cool. As you ride the truck through the streets, you can shoot groups of enemies with your grenade launcher. You also have a rifle, with another grenade launcher on it! That's a lot of grenades. However, shortly after you start, you'll find out why you need them as trucks give chase to your vehicle. Turn around and take them out with grenades before they take you out.
After taking out several trucks in succession, you'll get a little break. Shoot the enemies ahead of the vehicle, then the truck. You'll come upon a couple more trucks ahead, and then you'll get out of the vehicle. You'll have to do the second part of the mission on foot.
Inside the building, you may wish to switch to the rifle because of the tight spaces. When you get down to the ladder, throw a flashbang down first, then drop into the sewers and fight more enemies. Once you get down into the computer room, clear the area and stick the transimitter to the computer.
You'll have to defend the area during the download, and enemies will come from both sides. Some will even have riot shields, though those will be very useful if you get your hands on them. The enemies will alternate coming from each entrance, so take them out quickly before they start to build up. When the download finishes, grab the box and head back up.
You'll have to face a Juggernaut in the sewers. Use your grenade launcher to bring him down. Fight through just a few more enemies to get back up top and hop in the jeep to exfiltrate.

Smack Down
You'll be shooting from a helicopter at first. Take out the truck that's following you, then clear out the enemies in the first area with the aid of your grenade launcher. Afterward, check the roof on the right for more enemies. When they're all down, the helicopter will move on.
Take out the few enemies on the balconies and rooftops, and use your grenade launcher to kill the cluster of enemies on one roof. Shoot the enemy firing rockets at you and his two buddies on the upper roof. Continue shooting enemies as the helicopter moves, and before it's time to get off, quickly shoot the approaching truck with a grenade.
Now you'll be forced to jump down and fight on foot. To reach the drug package on the right, head up through the first accessible building and take the ladder to the roof, then jump from roof to roof to reach the one with the drugs. Blow the drugs up from a safe distance with C4.
The enemies won't be happy about this and will call in reinforcements. Now head into the opposite building and simply take the stairs to the other drug package. Blow this one up too, and get out of there, heading for the helicopter. Take out a few more enemies and run to the helicopter to complete the mission.

Flood the Market
You start the mission with the XM25 grenade launcher in your back pocket. You'll need it too, because in the very first area, there are waves upon waves of enemy soldiers. When the enemies stop coming, head into the stock exchange building.
Refill your ammo at the ammo box, then use your XM25 take out the enemies on the main floor of the building. Take the first of the encryption codes inside, and another wave will invade from the stairs, so quickly turn around and take them out.
There are two more codes in here to collect while engaging waves of enemies. When all three are in your possession, head up to the roof to upload the data. Plant the transmitter, then engage the enemies shooting from the opposite building. Take them out from cover before they start using their gas grenades against you.
Shortly after starting the download, a wave of enemies will come from downstairs and make life a lot harder for you. Find somewhere to hole up until the download completes, because when it does, the mission will end automatically.

Fire Mission
This is the more annoying of the two co-op missions, but thankfully it's very brief. The premise is simple: the player on the ground must advance while the player in the air must shoot the scores of enemies attacking the advancing player.
The player in the air basically decides if the player on the ground lives or dies. First off, don't shoot him, obviously. Secondly, be sure to take out the enemies he's trying to advance through, as there's no need for him to have to even fight most of them. Just aim for the area ahead of your teammate and wipe it out, then switch to another weapon to avoid having to wait on the weapon's cooldown. If you see a truck or a helicopter, take it out quickly so your teammate doesn't get himself killed.
The player on the ground should be careful not to advance too quickly, or he'll be too close for the player in the sky to shoot the enemies. Simply keep your distancek, let your ally eliminate most of the enemies, and pick off the stragglers before continuing. When you reach the objective successfully, you'll realize just how short this mission actually was. Enough friendly fire accidents can make any mission seem long.