If you helped out both Granny Rags during High Overseer Campbell and Slackjaw during House of Pleasure, then you will have an extra thing to do during The Flooded District. You will not be able to get through the sewers without the Master Sewer Key, which just happens to be in the possession of Granny Rags.
When you first arrive in the Old Port District area, go forward and talk to the thug that is injured. He will mention about being attacked by a lot of rats, as well as Slackjaw following them. Start by going onto the red pipe and following it. Keep following this path, noting that there are some River Krusts on the way.
Eventually, you'll have to swim to continue forward, and it's going to be a long swim. About halfway through a tunnel, you will see an opening in the ceiling, so use it to replenish your air, then continue on and up to the surface. There are stairs leading up, so go up them and follow the path, going through the door at the end.
You'll come across Granny Rags holding Slackjaw captive, and you will have to choose a side. Before doing anything, familiarize yourself with the surroundings and also note that choking out Granny counts as a kill, negating the Clean Hands achievement/trophy. Up the stairs is a bedroom, as well as the means of escaping this area after you finish.
| NOTE - If you are going for the Clean Hands achievement/trophy, then you cannot use a Sleep Dart on either person, as well as not choking out Granny Rags. This is most likely a glitch. If you're going for the nonlethal way, it is advisable to stop time, steal the key from Granny Rags and then hightail it to the water to escape. |
HELPING GRANNY RAGS
Talk to Granny Rags and agree to help her. She wants you to incapacitate Slackjaw, so go up to him and slash him with your sword. After that, ask her for the key, which she gladly hands to you, using it to free Slackjaw from his restraints. Pick up his body and throw it in the tub, which will finish the mission for Granny Rags. She rewards you with a Rune, which is located upstairs, on an Outsider Shrine (you can get this by helping either person).
HELPING SLACKJAW
When you first come into the room, go and talk to Slackjaw, agreeing to help him. You can also attack Granny Rags, which will make Slackjaw mention that you need to find her Cameo. Granny Rags cannot die and will just Blink around the area, calling rats to attack you as soon as you attack her or agree to help Slackjaw.
Go upstairs and into Granny Rags' bedroom, where you'll find her Cameo underneath the pillows on her bed. Take it and open up the incinerator nearby, placing the Cameo inside and reigniting the incinerator. This will destroy it, and make Granny Rags vulnerable to damage. Note that choking her out here will count as a kill for some reason. Once you get rid of her, talk to Slackjaw to receive your reward (500 coins).
