Bianca Steeplechase

'' You know the only difference between us, Red? You do this for the glory-- while I do it for the love. ''
 * -- The Joker src

History
Bianca Steeplechase was a ruthless gangster also known as the Joker. During the dynamic duo's final case, Bianca framed Bruce Wayne for the murder of Selina Kyle, and killed Robin with a fatal kiss (tongue was dabbed with poison). With Bruce on the run from the law, and Barbara in desperate need of a partner before she goes on the verge of a mental breakdown, they become a team, with Bruce donning the bat mantle. As for Bianca Steeplechase, she's dead. All there's left is Mrs. Gregory Wilson, the new wife of the mayor.

Abilities

 * Toxicology: Bianca has a penchant for poisoning her cosmetic products. She poisoned her nails and sliced at her enemies and even poisoned her lipstick to murder Robin.
 * Leadership: Bianca is a ruthless gang leader, coming up with schemes and plans to sew her influence and have her fun.
 * Singing: The night of Robin's murder, the Joker was singing to entertain a crowd of onlookers.