A virus plague most of Equestria. Turning most ponies into different creatures. Not much is left after the fall of Canterlot, the Crystal Empire, and Ponyville. Twilight Sparkle is the last known Princess. No one knows what happened to Celestia, Cadence, or Luna. They disappeared after the fall of Canterlot. Can Twilight somehow find a way to save everypony or will she and the remaining survivors succumb to the virus? Only time will tell.