Mission 8: Third Echelon HQ
Hug the left wall of the parking garage and jump up onto the security room roof. Aim down and double tap both guard and drop in. This will get you the keycard. Open the door and wait for the camera to pass by then run left and over the ledge. WAIT. There are two guys. One will walk away. WAIT. He will stop and look back. When he finall continues away, Death From Above. Hug the shadows on the left and headshot the guy who was walking away. Then head to the left end and headshot the guy in the back right corner. Make sure to kill him here so as to avoid camera detection. Then jump over the pillar and go left to pull yourself up to the shaft and head in and plant C4 #1.
Back out the shaft and to the lower level. There may or may not be a new guy down here. Headshot if you is once he's in the shadows. Then all the way to the far end of the lower level and behind the car is another air shaft to take you to the 2nd Generator. Plant the C4.
Back out to the lower level a third time and hug the shadows until you get to the middle. Wait for the camera to pass and then move to the middle and take the elevator down.
Walk forward to the receptionist and once the action starts duck down and eliminate the guard. This is a timed area and you need to get through the gates. Head through gate one and 2 enemies will appear. If you have a M&E it will be easy, otherwise just tap them in the head and slide under the gate.
This level has a lot of separate non-connected areas. Meaning you can really just run through and no one will chase you. I got a little lazy here and did a lot of running. I'll point out where to do it and how easy it is. It saves a LOT of time and hassle.
As you head downstairs hug the wall and wait for the bad guy to enter the room. Follow him in and do a Takedown. Then back to the hall and M&E the two there. Then Takedown the guy in the left room.
Move into the server room and jump and pull yourself up to the roof area. Headshot the guy on the right and then drop down and go into cubicle area 2 from the right. One guy to headshot on the left and then Takedown one in the back right and then move on.
Down the hall and headshot the guy across the way. Hug the corner to M&E the two at the end of the hall. Then head through the offices on the left to bypass the camera.
Third Echelon HQ - The Garage
Head into the server room to talk to the tech.
After the conversation pull yourself up to the roof area and work your way around doing Ledge Takedowns. Use the sonar to mark positions even if you are not going to M&E to show you enemy movement.
Watch the camera as you leave the area and go back to the 2 cubicle area. I bypass this area by getting on the roof area, and then running top speed past the first area and down the hall. Just was tired of these rooms at this point.
Back to the first area you were in downstairs. Silently get to the far window and then just shimmy all the way to the left. Get out and sneak up the stairs bypassing everyone again. There may be a guy at the end of the hall to Takedown.
Laser beam time. Equip the Sonar Googles and see the path. Crouch under and head left going through the two sets of beams when they are over your head. Then jump over the planter on the left wall. Then under the beam and over the next planter. Wait for the beam to go up, then wait for the next set of three to turn off one at a time. Then crouch around the corner and through the lifting beams and you're in.
Head upstairs and interrogate Kobin for the second time.
First you have some high levels to take care of. They have sonar too. Just wait for them to come to you and unleash.
Afterward crouch at the base of the stairs and headshot the lower level guy coming at you and the one at the back right. Then Takedown the left side.
More beams. Head into the left room and jump over the three sets of benches. Climb and over the wall. Then up over the center planters and crouch in the middle till the beam goes over. Then over the last planter and out the door.
Third Echelon HQ - The Office
Head into the left side offices and crouch stalk the one guy over here until you can get to him for a Takedown. M&E as many of the guys as you can. You can head right into the small offices for another Takedown to get more M&E or head left behind the whole area for a different approach. When everyone is dead you can head up the stairs.
At the top is a high level attack again. So expect to be seen and just take them out one by one. Remember to move safe and keep going so that your last known is a good distance away.
Then head into Grim's office.
Afterward you get unlimited M&E so it's a good time to go for your 15 kills with an assualt rifle. Just DON'T reload your ammo during the sequence. There are 17 enemies so you have enough, just not enough to screw up.
Third Echelon HQ - Grim's Office