Corvo and Emily are heroes; however, being a hero does not necessarily mean you will have to play by the rules and be the Mister or Miss Nice some people think you are. Dishonored 2 allows its heroes to solve their problems using the most clever way possible, even if it means looting the Black Market. Well, it's the Black Market run by thieves so you're just giving them a taste of their own medicine. However, before you can even do that, you need to find the Black Market key to give you access to that place. Here's how you can do that.
Your first encounter of the Black Market will be during Mission 2 called The Edge of the World where you will be tasked to find the Addermire Institute. You will also be asked to locate the Black Market as an optional objective but first, you need to find the Black Market Key.
First, follow the marker that leads you to the Black Market Shop. When you get up the stairs, climb out of the window on your right side. On the rooftop, locate an old building across. This building has been quarantined because of bloodflies infection. Run to the top floor and go into the room with the missing chunk of wall. Crawl into what used to be a fancy residence and locate the barred door. This will be on the left side of the piano.
After that, climb on top of the dresser that blocks the door and crawl through the gap which will lead you to more stairs going up. Go to the floor upstairs but be careful because there's an infected inside. After killing the infected, locate the blue aquarium and smash it to retrieve the Black Market Key.
You can go out from the room where you are by smashing the window and jumping down. Get behind the Black Market Shop and slowly pass the sleeping person. Unlock the Black Market Shop using the key and find some very useful items there.
Inside, you will be able to acquire two grenades, a sticky grenade, a pistol, and some bullets. You will also acquire a bloodcharm inside, just don't kill the shop owner.
