A Dark Knight: The Sinking Ship, The Grand Applause - S4-E15
Continuity mistake: Bruce begins to turn to face Selena twice as she speaks to him about searching for a fenced item she needs back.
A Dark Knight: Mandatory Brunch Meeting - S4-E17
Continuity mistake: Jerome's shotgun switches position from his shoulder to being held at waist level several times as he questions the people about Xander Wilde.
A Dark Knight: Mandatory Brunch Meeting - S4-E17
Continuity mistake: Jerome's pistol changes position between shots as he points it at Jeremiah's head.
A Dark Knight: That Old Corpse - S4-E20
Continuity mistake: The frontal shot of Gordon shows Echo holding her gun to Gordon's head with her finger off the trigger, but the next closer shot now shows her finger on the trigger.
A Dark Knight: One Bad Day - S4-E21
Continuity mistake: After Selina and Bruce kiss, she takes her hand off the back of his neck and lowers it. In the next shot, her hand is back on his neck and she lowers it again, and then it's on his shoulder.
Legend of the Dark Knight: Ruin - S5-E4
Continuity mistake: When Ed is trying to take the Blackgate folder from Lucius, the way it's held between them changes between shots.
Legend of the Dark Knight: Pena Dura - S5-E5
Continuity mistake: When Gordon jumps onto the bench in the library, he grabs the 2nd shelf as he's falling backwards. In the next shot, he's holding the 3rd shelf.
Answer: "The Merc" was a warehouse like store with aisles that sold mainly weapons, machetes, AK-47s, C-4, barrels of acid, etc. In s02e05, "Scarification", it was shown being raided by GCPD.
Bishop73