Hey guys!
I just thought about a what if theory. What if the Snow Queen actually existed before Elsa's birth, and after she got defeated by Kai and Gerda she pulls out a same kind of thing that Zelena did after she died(?), but during it she remained alive and posessed Elsa when she was a child, or when her mother was pregnant with her. So basically what if Elsa has the Snow Queen inside her, this would explain her huge power that she cannot control and kinda acts on its own. (For example in the Frozen movie, there is a scene where some soilders tries to capture her, and one of them shoots an arrow. She only covers her face, and her powers automatically acts and pulls up a small barrier that protects her. Elsa also looked very suprised by this) And in the past maybe Rumple awakened this side of her, but she was more powerful than he thought so the best he could do is capture her in that urn.
This would mean that in S4a The Snow Queen would be the villain in Elsa's body, and the goal would be defeating the Snow Queen without actually hurting or killing Elsa. What do you think? (Sorry for my English, it is not my first language ^^ )