Board Thread:General Discussion/@comment-23902651-20131007194808/@comment-23902651-20131009201618

I thought that at first too (when the episode first came out). However, I think it's more complicated than that since the show is very intentional about costume changes and behavioral change consistencies across the episodes (since there's so much back and forth). I think she didn't want to use dark magic throughout Snow's childhood and she wanted the King to actually grow to love her, since she seemed so disappointed at the King's birthday party. Then when she realized he'd never love her, and she killed him, that pushed her over the edge to be able to fully use dark magic.