Venus

Based on a venus fly trap. 

Story: Venus is basically an advanced plant from a planet where the plants are alive. Her form mimics that of humans to trick them. She basically wants to turn Earth into a giant jungle for her to feed off of. Earth is rich in nutrients and more tame than her home planet. Basically this means lots to eat and no competition. Poison Ivy and Mother Nature are kinda arch nemeses, because their powers overlap a bit. They both can control planets.  However, Mother Nature mainly works with animals and can only cause plants to grow or bloom a little bit. Ivy has no control over animals, although she can make sentient plants, but has immediate and STRONG control over plants. It takes both of these girls teaming up to stop Venus.