In the previous chapter, Nate and Sully ventured into the lost city. Sully got shot by Talbot, and you chased him deep into the heart of the city vowing for revenge, and hoping to uncover the mystery of this Atlantis.
This is the final chapter!
At the bottom of the spiral staircase there will be a short cutscene. Head on the path, jumping over the gap. Kill the bandit that comes to greet you. Watch out for the laser beams, there will be lots of snipers shooting you from structures across. Use G-Mal, Grenades, and Tau Sniper a lot in this battle. The SAS-12 and M32 - Hammer can also prove useful.
Climb up the stairs, killing any enemy you come across. Keep going, neutralizing the enemies that shoot at you from behind the wagons. You will reach a room and a cut scene will begin. You see Sully again. You are not sure if he is real or not. He hits you to prove he is not an illusion. You are not sure what is going on because you saw Talbot shoot him right after the Eclipse. But Sully tells you that the Eclipse never happened, and that you went nuts after drinking from the fountain and the whole thing was your imagination. The water is what destroyed the city. Not the wrath of god. The whole water supply is tainted with some sort of hallucinogenic agent. Must have drove everyone mad. That's what Marlowe and Talbot are after. They control their enemies through fear. But how are they getting the water out of here. They are after whats in the water. Power to control people through confusion and fear.
You have to find a way down there to end this thing. Go to the platform with the lever. Turn the lever counter clockwise with Sully and the elevator will go down.
Cross the courtyard and up some stairs. Sully will help you with a door. Reach a big room with a cobra statue. There will be some enemies in this room. Kill them. Keep going, head down another staircase. You'll have more company in the floor below. They will shoot rockets at you so take cover. Watch out for snipers and rocket fire from the rooftops.
Reach the yard that has a metal crate in it. Open the crate and you will find some diving equipment inside and a pistol which Sully will take. Open another door. Keep working your way through the city, passing a street with some gears.
You will arrive at the water where Marlowe is working on extracting the hallucinogenic agent from the water. You have to take that crane out. But you are outnumbered. Split up and try to flank them. Better odds that way.
Talbot will aim his pistol at you, but Sully will surprise him from behind. Talbot manages to overcome Sully and throws him in the water. Jump in after him.
Observe a container that is being lifted out of the water.
Shoot towards the surface of the water destroying Marlowe's machine. The building will start crumbling. It looks like the whole place is coming down. The enemies don't seem to care that you are all going to get buried and will shoot at you. Kill them as fast as possible, for you must exit the city. Go back through the cogs. Watch out for more sniper fire and rockets. Use the big cog as cover an shoot enemies from behind. Keep moving. rotate the level with Sully to make the platform go up. There will be more enemies waiting for you when you arrive at the top.
Climb a ladder up. Note the gears that are moving. You will have to ride the buckets up. Climb some more ladders. then head up a stairway shooting the bandit that's on top.
You will now run into Marlowe and Talbot. Talbot will point his gun at you. But the floor will collapse beneath you. Marlowe is trapped in the quicksand and Talbot can't reach her. She calls out to Nathan. Your conscience will not let you leave her to die. You try and save her, but fail. Marlowe, along with Sir Francis Drake's ring, are forever gone.
Ok it's time to start running. The whole place is coming down. Up the stairs, and jump across the platforms. You are in a sinkhole! keep running and jumping. You are almost out. As you are about to exit the city, you are attacked by Talbot. This is a BOSS FIGHT.
Talbot takes out a knife and stabs you. You roll down to the chasm, grabbing the edge of the floor with your hand at the last moment. Talbot tries to step on your hand to make you lose your grip. PRESS TRIANGLE IMMEDIATELY. Go back up on the ground and keep fighting Talbot. Follow the onscreen prompts to perform counters and escape Talbot's grabs. Stay away from the edges so that you don't fall down.
Sully will shoot Talbot, and you will fall down a bit and hang out onto the cliff. Sully's gun will fall, catch it. Talbot and Sully will struggle above. Talbot is about to hit Sully with a heavy object. Aim at Talbot's head. Shoot and kill him. Jump to Sully. Follow him and escape the city. Salim's men will show up. Jump on the horses and gallop out as the city collapses into the sand.
Closing cutscene. You and Sully are in the airport and head back to the airplane. Sully tells you that you don't get to choose how you start in this life. Real greatness is what you do with the hand you are dealt. He gives you a ring. Elena shows up. You propose to her. Sully leads you to a plane, as you embark an a new adventure.