During a recent accident, Pinkie Pie was forced to go to the hospital where she was exposed to X-Rays...she then discovered she was more than a normal mare.
A school assignment leads Dinky to question why she's never met her mother's parents.The truth of the matter being that Derpy hasn't spoken to them since before she was born.
Applejack, despite her best efforts, has been watching red ink replace black in the farm's ledgers for over a year. She can't see a way out of her financial problems or the growing depression threatening to cripple her.
Luna has been redeemed by the elements of harmony, but is finding that salvation is harder to come by. Perhaps the Moon, her prison for so very long, is truly where Luna belongs after all.
After losing their magic, the Dazzlings are hit hard by shame and sadness. None are more hopeless than Adagio Dazzle, who loses all light in her life and begins to sing a swan song. For sirens, this is suicide.
Octavia has a secret, and its that shes mentally insane. And as if living with a sociopathic voice inside her head wasn't hard enough, now she has to stay under the same roof as Vinyl, arguably the most insane pony in Equestria.