The Corrupted Soul

Dryad a powerful creatures living in the magical forest, they can shift a form of a tree or a human. They intend to give a divine justice to anyone who create a scenario in the forest. Or to anyone who harm their trees. They are pure and kind, but suddenly one Dryad became pure evil. It harms anyone who bothered to go to the magical forest where she lived. All the creatures living there turns to be all evil. No one can ever enter it or leave. And all of the Kingdom near the forest are terrified about it. They plan to raid the forest and kill the evil Dryad living on it, so it will bring peace to the world. But one Kingdom choose not to use any harm on fixing that problem, they find a way to enter that magical forest with the help of the other Dryad.