Jump across to another walkway, then cross another beam and jump to still another platform.

Head down the walkway in the direction you start out, and cross the beam at the end to another platform. After the cut scene, you and Elena will split up, with you going to the tower after the dagger and her looking for the secret entrance to Shambhala. Keep going around until you come back out into the main part of the building, then head up the stairs where you'll find SchГ¤fer. Go through the room and out in the hallway, then go into aim mode and walk toward the next room ready to take out the guard that pops out from the left. Head around the inside of the building along the wooden walkway and enter the room at the end. Take them out, then head upstairs and kill another guy across the building. When you've taken out the last of them, two more guys come from the wall across from where you entered. Take out the guy coming down the stairs, then face the opposite direction across the building and get cover to start taking out the bad guys over there. Head around to the stairs, and another wave will start. There's another guy with a missile launcher above and to the right of you, so head away from him along the available cover, until you turn the corner at the end of the room and can take him out. After you clear the first wave, there will be a brief respite, then an RPG gunner will come down, so take him out. The guys come from both sides and are reinforced by more enemies coming from above.

Grab cover behind the wooden railing right in front of you and start taking out guys, beginning with the laser scopes.

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