Pamela "Poison Ivy" Isley was a super-human foe of the Batman.
Pamela Isley did not have a very good childhood, with a rare skin condition forcing her to spend most of her time inside and a father that beat her mother. Eventually, her father killed her mother and she was taken into foster care. Later, when Pamela was accepted into an Ivy League university, she began to experiment with plant pheremones, making them pills and selling them as commercial drugs. Pamela was almost arrested once, but managed to avoid it through hypnotizing the School Dean and graduated. Insanity began to emerge in Isley around this time. She confronted her father in jail and poisoned him by secreting a potent toxin from her lips, carried to her dad by a kiss. He died in his cell the next day from "heart failure". Isley then applied for a job at Wayne BioChem, but after Bruce Wayne found moral issues in her thesises she got fired. During a scuffle with security while trying to steal back her work, Pamela was doused in chemicals and was given Metahuman powers over plants. With that, Pamela became the villain known as Poison Ivy. She was, however, quickly stopped by the Batman, though she managed to escape from her incarceration at Arkham Asylum. In spite of her insane criminal and murderous nature, Black Canary chose Ivy as a member of the Birds of Prey. Though the group would stay intact for a while, Ivy eventually relented back to her old criminal ways and turned on the Birds. However, she was defeated by Katana and left for dead, though she survived and decided to hatch a plan against polluting factories in Gotham City.
Manipulating Clayface Using herbs to control his mind, Poison Ivy launched a series of assaults against the pollution factories of Oswald "The Penguin" Cobblepot. However, she was captured by Ignatius Ogilvy who ended up freeing her. Her plan failed, Ivy was shocked to find Clayface out of her control and out for revenge, however, once again Ogilvy saved her. In return, Ivy ended up aiding Ogilvy in creating a serum strong enough to physically enhance the man into a Metahuman. When Gothtopia was launched, Ivy found herself immune and managed to use her thorns to snap the Batman out of the illusion. She was then seduced and tricked by the Batman, who used her to gain immunity to a new strain of Fear Toxin. Following, Ivy was let free to go.
Ivy was later contacted by DEO and told to work alongside the Riddler, Mad Hatter, Tweedle Dee and Tweedle Dum under Bane to take down Batman. Ivy was told to do this without killing anybody. Later, when the Crime Syndicate took over Earth Prime, Ivy was allowed to send madness off into the streets however she pleased due to her membership in the Secret Society.