Board Thread:Spoilers!/@comment-1916997-20180303031455/@comment-32092932-20180304184749

I agree with CoolDudeAI's theory. However, I think it could also be a [Witchcraft|witch]] who doesn't like other witches and possibly someone from ]]Storybrooke]].

Witches who stay in Storybrooke
 * Zelena (formerly, but she traveled to the New Enchanted Forest in "Secret Garden to save Robin and was brought to San Francisco by the Dark Curse.
 * Regina (formerly, but she along with Hook traveled to the Tremaine Estate to save Henry from Rapunzel Tremaine.)