Backstories Wanted!

Characters I would love to see get a one-shot (or in some cases a limited-edition series) backstory/history/coming into their powers issue. Or better yet, find a way to get Marvel to let me write one because I don't think fanfiction would do them justice and I have ideas for most of them. 
   - most of them are character from Xavier's Institute, I know, but there were so many of them that were created for just that and never went any further.

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