The Abramovici Twins (Gotham Stories) - Batman: Arkham City (2011)

Andrei Abramovici was a respected man in the small Siberian village where he lived with his pregnant wife. When word reached Andrei that his wife was in labour, he rushed home, excited to be at her side, but was met only by the midwife. His wife had not survived the birth; complications due to the special nature of his newborn sons were to blame.

Pushing into the room, he found his twin sons, joined at the shoulder, screaming for their mother.

He took the twins and left town. Crying, he stood on a bridge over the freezing cold river and contemplated throwing them to their deaths, but he could not do it. Leaving his sons outside the tent of a travelling freak show, Andrei returned home to his village a broken man.

The Joker heard tales of the conjoined Abramovici twins, now widely known as Hammer and Sickle, and their reputation for brutality, and he wanted them for himself. Sending Harley on a desperate mission to retrieve them, she passed on the message to the circus owner that her puddin' would pay big for the twins.

Of course, the owner refused to sell his headlining act. He promptly vanished, only to be found three months later with a new smile carved on his face.