Faith needs to head down towards the rail system; however the Blues are already waiting. Wall Run to the two red pipes, and slide down them to ground level. Leave the alleyway and hop the fence, climb the red pipes to get on top of the blue catwalk.
Continue up the blue stairs to the top of the building, jump from the plank over the fence, and move left.
It's safer to deal with one enemy at a time, than take them all at once.
Climb over the duct to the far left and disarm each Blue one at a time. After the coast is clear, move up the pipe and take the zipline to the next area.
On the next roof will be a red door into the building. Enter the the door, and inside will be an open elevator shaft with red pipes. Jump to the pipes and slide down below.
Down the hall will be another red door, move through it to an exterior stairwell.
You'll need to get on top of the roof on the right. Wall running is the only option of getting across.
The shotgun is far too deadly to confront both of these enemies at once.
Use the zipline to reach the fans on the next building. Be careful to not let go early, as it is easy to fall to your death.
You can use these air-conditioners to get on top of the roof.
Move forward and into the alley to the far left. Use the trash pile to jump up and cling to the ledge above, the jump to the bar behind and swing to the duct. After climbing through the duct, move through the next two red doors and into the mall. Follow the Mystery Runner into the mall's main area, that will be filled with Blues.
The window can only block a few shots before breaking.
Once the elevator jams, break the glass if it's still intact, then leap out and into the hall to the right. At the end of this hall hop the rail to the area below and up the escalators.
Climb the lockers on the left to enter the duct above.
Use the duct as a bridge to get to the other side.
The box ahead can be used to cling to the ledge.
Use the button to turn of the e large fan.
Once safe, move into the duct to the left, then drop down, and take the stairs up. Climb the red pipe in the next room, and through the red door to finish the chapter.