thanks for the new thread.
maybe in that episode, there are scenes about :
1. a flash back to the time the same as in the "welcome to storybrooke", where it tells us about snow queen & emma flash back:
- when snow queen came to storybrooke and how she came there (because she didn't come because of the curse), and
- when Emma & Snow Queen knew each other at that time. Snow Queen maybe a foster mother of Emma, or a person who plannd to be a foster mother to Emma, or snow queen was the person who run the foster home where emma was in that foster home
2. in the present time: they all fight the snow queen, and they won.