To the Tower is the ninth chapter of Drake's Fortune. Nate and Elena continued their search through the Drowned City for the tall tower from which they would be able to enter the customs house.
Story[]
After traveling further through the flooded ruins, Nate and Elena soon reached another drop-off point. Nate went alone to find a way to the tower, while Elena returned to the customs house, expecting Nate to meet her there. After several gunfights with pirates, Nate finally made his way to the top of the tower. Using a cable as a makeshift zipline, he slid down through a large hole in the roof of the customs house, then opened the door for Elena. After regrouping, the two continued on to find the escape boat.
Walkthrough[]
Nate and Elena are en route to the tower.
This chapter is a continuation of the previous one, as you are still in control of the jet ski. The same rules apply—kill the pirates and shoot the barrels that stand in your way. Continue to follow the linear path until you reach a gate, at which point you will need to shoot the chains on either side to lower it. Once you are inside and you dock the jet ski, Elena will leave, leaving you to explore on your own. Two normal pirates and one wielding a Moss - 12 will ambush you, but they are all easy takedowns. You can also find two Mk-NDI grenades lying around before you head to the next area.
Nate protects himself from more pirates.
To reach the next area, you will need to swim through a narrow path of water. As you do so, enemies will attack you head-on, so once you make it across, take cover immediately. Try grabbing hold of the ledge at the end, and hang off of it to pick off any nearby enemies before moving any further. You can find another pair of grenades on a crate in the lower-left corner as well. Once you take out this group, climb a small set of stairs, after which you can jump onto a nearby balcony platform, and then on top of a broken wall. From here, jump to the next wall and pillars until you reach the top of the locked gate, at which point you can simply drop down and immediately engage the next set of combatants.
You should immediately take cover, as a pirate wielding a Moss - 12 and another wielding a Wes - 44 will ambush you from close range. Be careful upon going through the first opening on the right, as a pirate with an M79 will be ready to blast you right away. Mow down him and any other nearby pirates, then deal with the group entrenched in front of the tower. The M79 will be useful here, but it can also help to simply hang onto the buildings and use them as cover. This allows you to save the M79 for the final group that emerges from the tower all at once.
Nate ascends to the top of the tower.
Once you have killed them all, you can continue to the open tower entrance and head inside. There are a couple of remaining pirates in here, who can easily be dispatched with melee attacks. Once cleared, you can use a nearby lever to move a chain, which you must then climb to reach the second floor. Once there, climb a series of white-marked handholds to reach another lever, followed by using the same handholds and a pair of tiny platforms to make your way around the room to reach the second chain. At the top, a single pirate will ambush you, but he is otherwise easy to take down. Afterwards, go around until you reach the stairs. Climb them to get to the top, and you will see an opening at the edge. Press 
to descend the wire leading down into the roof of the customs house. Once inside, you will hear Elena's voice from outside, telling you to let her in.
Head downstairs to the door and shoot off its lock, then press to open it. Note that taking too long to open the door will lead to Elena being shot down. Once the two reunite, the next chapter begins from here.