The Mistake Evil Made:::(an OUAT surprise crossover)

Summary: Henry knew a girl. He grew up with her. The strangest thing, like the witchling friend of Attila the Hun named Galen. Beaten down, kicked, bullied and every time she got back up. When the first curse broke, her 'family' came for her and he never saw her again. Not until now...when the worst of the worst came and a single faceless girl in a funnel of magic stood up.
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Face-Cast: Deborah Ann Woll as Fiona Emilia Macintosh; descendant and reincarnation of Merida's mother's youngest sister (she married into Macintosh's family and their descendants took the man's name as a surname).//AN: A note about the OC's name, I put it here in the description even though it is never given in the oneshot. It is because this is the first of a series and a cookie to whoever can guess the crossover from the cover and a 'blink and you miss' note in the oneshot. Oh, and when you drop a comment, don't be a meanie.