Poison Ivy

"'Nature...always wins!' -Poison Ivy to Hulk"

Pamela Isley, also known as Poison Ivy, is a reformed supervillain and an old rogue of Batman as well as Hulk's ex-girlfriend/best friend.

After her death during the Arkham Knight Incident, Hulk dripped a drop of his gamma-irradiated blood on the large flower that bloomed on her ashes, reviving her and giving her a new body with vastly greater power than before.