A little piece of Earth arrives in Equestria, a human and it's home. The citizens of Ponyville and Princess Luna struggle with this newcomer, as it struggles with them.
Twenty years before the Elements of harmony, before Nightmare Moon's Return, Celestia started a whole new slew of problems and headaches for herself and the ones around her. Thankfully Cadence doesn't mind foalsitting.
Twilight has fun playing a virtual reality game with her friends, adventuring across an ancient Equestria, until she learns of players never waking up.
Trixie appears once more in Ponyville, babbling about how she is supposed to be the Element of Magic and how Celestia is the evil Tyrant Sun. Has she gone insane? Or is something larger happening?