I don't think Shadowheart is evil, probably neutral. If you kill all tieflings in the grove and read her mind at goblin's party after, you discover that she feels guilty and sad but she tries to hide those feeling even from herself. I have a theory that she was a cleric of Selune but was deceived by Shar.
It's great that many people have this theory.
I really hope that Larians will see this discussion, and make a quest where she will deal with her head and decides to be a cleric of Selune or a cleric of Shar, or both (lol)
Although most likely it was already planned, we just guessed ahead of time
I propose to think about what loss Shadowheart suffered as a cleric of Selune, the circumstances that led her to Shar. Perhaps she had someone dear to her who was killed because of Selune?
