Chasing a mystery into the past, Twilight finds an Equestria that is different from what she remembers. Will she be able to set history back on track by fixing what didn't happen, or is this Equestria destined to take a different path?
Pegasi have been pushing clouds around the sky and breaking them up for years and they never really worried about where the clouds went, or who it would anger. They also weren't prepared for war.
Everyone's a changeling. You, him, her, that. If it moves, it's a changeling. If it breathes, it's a changeling. If it's alive, it's a changeling. And Chrysalis is utterly sick of it.