Mission 3: House of Pleasure
Enter into Dr. Galvani’s house and make your way up to his laboratory where you found the rat viscera in the previous mission for Granny Rags. Open the bookcase and now where the rat was earlier will be a rune for the taking.
When you reach the Golden Cat, at the street in front of it, there will be a building on the right hand side that you can enter. Blink up to the second floor and find the rune on the table there.
Once inside the Golden Cat, when you reach the second floor by taking the main set of stairs, you will find the next rune on the wall in a frame before going through the door to the large center area.
When you are at the second floor landing atop the main set of stairs, turn around and you will see an opening of arches at the top of the wall. Here you can blink up and go through to find another dilapidated staircase that leads to the third floor. Go up and then make your way to the right down the hall there. Enter the first door and the rune will be on the right side on a table behind the woman smoking.
For the final rune, when you are in the Golden Cat, you can shock the Art Dealer who is strapped to a chair to get the combination for the safe that is located on the third floor of his apartment building. Once you have the code, return to the Art Dealers building in the Distillery District—the door is located next to Griff atop the stairs—and use the code 879 to open the large safe door. Once inside, the rune will be on the left side. Note that you need to get the key to the Art Dealers building first from the woman you save from thugs atop the stairs at the left end of the lower alley in the Distillery District.