Poison Ivy

Poison Ivy is a character created by Robert Kanigher and Sheldon Moldoff and is part of the larger DC multiverse. She usually is an adversary of The Batman, but will also bother just about anyone she can blame for destroying the environment. She's sort of like Captain Planet with heels and a bloodlust.

New 52
Ivy picked up a new costume in the New 52, made out of a substance that heals itself in sunlight. It can also form tentacles. Briefly she joined the Birds of Prey until she turned on them and blackmailed them into being her personal ecoterrorism army. Eventually they cured her pathogen and believed that they had killed her as well. As with most super-characters it didn't take.

During the Rotworld storyline of Swamp Thing/Animal Man she appeared, working as one of the champions of the Green. She survived until the final fight against Arcane and the Parliment of Rot, but her final fate was unknown as Swamp Thing and Animal Man leapt into the past before the fight's end.

Other Media
Poison Ivy made occasional apperances in the Batman: The Animated Series, generally growing less antagonistic over the course of the series. This was also the series that debuted Harley Quinn and the pair's "are they/aren't they" relationship.

She was a boss in Batman: Arkham Asylumn.

Abilities
Ivy has often commited crime through the use of her genetically manipulated plants. Over time she became more and more plantlike, including having chlorophorm for blood as well as a touch that is toxic to mammals.