Modern Equestria doesn't need Flash Magnus out there on the front lines battling monsters anymore. And he's fine with that. He is. Really.
But when a matter arises that dates back to the earliest days of pony unification, Magnus finds himself calling upon skills he'd almost forgotten he possessed to once again save the day. With a little help from his friends, of course...
My entry in Shrink Laureate's Season 9 Bingo contest, this story got an Honorable Mention and was inspired by a set of images that I'll link to in the Author's Note at the end to avoid spoilers.