10 Things Everyone Always Forgets About Harley Quinn

At one point, when the Joker began to feel serious romantic feelings for Harley, instead of facing them, he shot her off in a rocket. She crashed in Robinson Park and was found by Poison Ivy. Ivy planned to kill her and, when the Clownette showed no emotion, Pamela had to know why. When Harls told her story, Ivy agreed to help her get revenge on both Batman and Joker. She took Quinn to her toxic dump layer and injected her with a serum that gave her immunity to many toxins, including Ivy’s, and gave the Clown Princess enhanced speed and strength.

Harley was so angry with the Joker that she even worked with Batman to bring him down. Quinn chased the Clown into an abandoned building and was going to let him fall to his death when Joker apologized. Harley immediately forgave him and fell in love with him again, and the two remained inseparable throughout the rest of No Man’s Land.

In Grant Morrison's Batman #663, Harley delivered poison-emitting roses to the Joker’s former henchmen and associates while the Clown was recovering from a gunshot to the face. Joker wanted to wipe away the old before he unveiled his “new self.” Quinn soon realized that she was part of the “old” and shot Joker in the shoulder, allowing Batman to capture him.