As soon as you gain control over Lynch, take cover behind the table to your left and click the Left Stick to crouch. Look for some gas tanks on a trolley next to the cargo container at the left end of the area. Target these tanks with gunfire to detonate them, with any luck killing one or two of the enemies in that area.
After the blast, quickly move out and take cover behind the wooden crates up ahead. You can't remain here long, as these crates are destructible. There are more gas tanks on a trolley at the back of the area you can detonate to kill a couple of the enemies covering there. After that, just use your shotgun to take down as many of the remaining enemies as you can. If the crate you're covering behind is destroyed and things are still too heated for you to move out, quickly take cover behind the second crate and continue picking off enemies.
Target the gas tanks at the back of the area to take out the enemies covering there.
Once things have died down, move up to the cement cover to your right. If an enemy manages to get close, you can blindfire by pressing RT/R1 while behind cover without holding LT/L1. There's also an acetylene tank at the base of this cover you can use to dispatch more enemies. You also need to keep an eye on the enemies to your right, as one may move to the piece of cover across from yours and be able to take shots at you. Your cover is indestructible, so keep behind it and use your shotgun to pick off the remaining enemies as they pop out from cover to fire.
The game will auto-save when the last enemy in the area falls. At this point, look for two gas canisters along the wall to your right. Sprint over to the cans, pick one up and then start toward the stairs at the other end of the area. Reinforcements will soon appear on the walkway. There's another trolley full of gas tanks below the walkway, so if you time it right, you can take out several of the reinforcements by throwing a gas can at the tanks and shooting it. Doing this will definitely kill the enemy reinforcements below the walkway. There also seem to be some explosives under the stairs, so you can run back, grab the other gas can, then move back into cover, throw the can at the stairs and shoot it to take out the enemies covering on the walkway.
Dealing with the reinforcements
Scour the area for weapons and ammo once you've dealt with the reinforcements. Pick up a shotgun and assault rifle, then proceed up the stairs, turn right and head down the stairs there. Lift the door at the bottom of the stairs to move on to the next area.
Sprint through the area beyond the door and stop when the game auto-saves. At this point, move forward and immediately take cover behind one of the containers here. Two enemies will reveal themselves on the walkway. Look for a gas canister on the right side of the walkway and detonate it with gunfire to take out one or both of them. If an enemy remains, keep behind cover and blast him with your shotgun when he pops out from cover to fire.
Proceed up the stairs once the walkway is clear and pick up one of the acetylene tanks at the top. Throw the tank toward the enemies covering at the other end of the corridor here and detonate it to hopefully dispatch one or more. You can fallback and pick up the second acetylene tank to throw if you wish. Move up and open the door at the other end of the corridor once you've dealt with the enemies there.
Start down the walkway and take cover behind the second large container you come to. There's an enemy covering behind the crate at the corner of the walkway, so blast him with your shotgun before moving out from cover and continuing down the walkway. Climb up the steps at the end of the walkway and turn left. Gun down the two enemies here and make your way to the other end of this corridor to trigger a cutscene.
You'll need the powerful weapons the army employs to make it through the latter half of the game.
After the cutscene, take cover behind one of the crates up ahead and dispatch the two soldiers by the stairs. The army employs powerful and accurate weapons, so swap your assault rifle for the Nianshi 500 submachine gun used by the two downed soldiers and then start up the steps. At the top of the stairs, take cover on the side and gun down the troops in this corridor before pushing forward. Swap your shotgun with the Buqiang 3000BP used by the army. You can press down on the D-pad to locate one.
There are more soldiers on the bridge, so move up and take them down from behind cover. With that, cross the bridge, turn left and start toward the other end of the walkway. Keep an eye on your left and stop when you come to an acetylene tank. Pick up the tank, throw it at the troops gathering in the area below and shoot it. There's another acetylene tank along the walkway you can use to take out the remaining enemies. Be careful, as one or more of the soldiers may have made it onto the walkway.
Clean up with your shotgun and then proceed down the stairs at the end of the walkway. If there are any acetylene tanks left in the area, pick one up before moving toward the steps up ahead. If you have an acetylene tank in hand, throw it at the platform across from the stairs and shoot it to kill the two soldiers covering there. If you don't have one, hang back at the top of the stairs and take out these soldiers with your guns before proceeding down the steps. Then, take the stairs up to the platform and walk around to the stairs at the other end. Gun down any enemies that are below and then pick up the acetylene tank by the crate at the bottom of the stairs. Take cover behind the crate and use the acetylene tank to eliminate some of the soldiers covering up ahead.
Push forward when the area is clear and put down the remaining enemies. Then, move through the doorway at the other end of the area and take cover. Scan the area for the Buqiang 800 assault rifle used by the army. This weapon has an ammo cap of 15, but is very accurate. There should be a scoped Buqiang 800 lying around, so press down on the D-pad to locate it and pick it up before moving on.
Use the Buqiang 800 to pick off distant enemies.
Move in to the next area and take cover. A group of soldiers will appear in the distance. Look for an acetylene tank on the left and shoot it when the soldiers near. Then, hang back and use your Buqiang 800 to pick off the remaining soldiers as the pop out from cover to fire.
Once you've dealt with the soldiers, move onto the walkway to the right and pick up one of the acetylene tanks along it. Proceed to the end of the walkway and move through the doorway at the end of the area. Take cover in the next area and throw the tank at the soldiers covering up ahead. Then, pick up the second acetylene tank behind your cover and move to the cover to your left. Hurl the tank toward the enemies by the stairs in the area on the left and shoot it. There's another acetylene tank here you can pick up and throw at these enemies as well. Clean up with your Buqiang 800 and then sprint up the stairs to get onto the walkway.
Cross the walkway and take cover behind the stacked crates on the side. Ensure there aren't any soldiers behind the cover by the set of stairs up ahead. Then, take cover behind the yellow board further down the walkway and start picking off the soldiers at the other end of the area. This last group of soldiers is blocking the level exit, so you'll have to take down all of them to escape.
There's an acetylene tank at the base of the yellow board you can use to kill some of the soldiers below. Other than that, just hang back and continue picking off the enemies below until the area is clear. Move out to the door at the end of the area and open it to complete the chapter.
Fight your way to the exit.