Aside from breaking Joker out of Arkham of her own free will, she continued being a sadistic serial killer, even after she was free of him. This version of Harley killed dozens of children with ...

A notable example of this was in Gotham City Sirens, written by Paul Dini and illustrated by Guillem March, where Harley attempts to break into Arkham Asylum to kill the Joker, only to change her ...