A recent list of Achievements hinted that an add-on campaign would be coming to Batman: Arkham City revolving around Harley Quinn, last seen in the game sobbing piteously over The Joker's death.
A teaser image has been released by the game's official Twitter feed showing a pair of boots that somewhat resemble Quinn's and a giant mallet.
Since it was released from the official Twitter feed, expect an announcement in the upcoming week.
