Find and rescue Basso | Chapter 4: A Friend in Need Thief Guide
Last update: 11 May 2016
From now on, Garrett will be experiencing serious problems with breathing and, as a result, this will result in a gradual depletion of his health bar. This means that you should walk through all of the successive locations, on this floor, as quickly as possible. Apart from that, remember about eating food, as soon as your health decreases to dangerous levels. Start by exiting the venting shaft. After you walk i9nto a new area, take a turn to the right twice and check out the corner near the flames and interact with the valve here.
By shutting the valve, you make the flames, which have earlier blocked the northern exit, disappear. Go North and, after you reach a fork, turn left. Use the Wirecutter n the box here and walk into the next room, quickly. Examine the chest here and collect two Watch Seal - 2x20G and a Magnifying Glass - 15G.
Do not attempt using lockpicks on the Northern door, because this would take Garrett too much time, even in the concentration mode. Instead, climb quickly to return to the fork and take the passage to the right, which you have ignored earlier. Climb onto the ledge on the left and take a look around to find a Flask - 4G and a Gear - 6G. Reach now the North-Western room, i.e. the one located at the locked door. Inside, you will find Food and a Magnifying Glass - 15G. Finally, interact with the valve shown in the above screenshot. After you give it a turn, crouch and leave this location. You can slow down here, because Garrett will stop losing health points.
Climb down the stairs and reach the door to the next floor in the keep [The Keep - Boiler Level]. You should take a look around, especially that there are no enemies in here. Apart from Food and a Flask - 4G Garrett will find here a ring (Memories of the Dead - Soldier's Memory) and a plaque (City Heritage Plaques - The Keep), which you can remove with the wrench. After you have explored this level, call for the elevator, enter [The Keep - Elevator] and ride towards the upper floors.
Wait for the elevator to reach the next level and star exploring The Keep - Prison Level. Also here, you do not need to sneak, because the guards either escaped or died in the fire. Explore this area carefully, thanks to which you will find a registry (Prisoner List), a Desk Bell - 12G and a Graven Letter. Finally, pull the lever on the East, which will free Basso, and start another cutscene.