Instructions
Run down to the platform ahead of you once Atem, your partner, leaves and tells you to escape through the hangar. Take out the enemies, then enter the hallway they came from. Look to the right of the platform, and aim your weapon down through the hole to kill the enemies there.
Get on the elevator and ride it down to the next level. Walk down to the opposite end of this path, then drop down to the catwalk below. Kill any enemies that appear, then drop down to the next level.
Run down the path to another elevator and ride it down to the next level.
Exit the elevator. Move to the left and look down. Shoot the enemies there and run across the beams to the other side of the hangar.
Drop down onto the platform sticking out of the building you're standing on and a big group of enemies will rush you. Take them out, then proceed along the platform to another elevator. Ride this one down to the bottom of the hangar.
Walk down the center of the hangar to the hallway guarded by two Survivors. Go through the hallway. Follow the linear path through the hall until you come upon a control panel. Destroy it to open the adjacent doors and initiate a cut scene. Once the cut scene is over, you will be outside of the Ark.