A few years after Luna's return it seems that Equestria will finally know an era of peace and appears to be on the verge of a new renaissance. Ponies are happy. Luna is recovering. Celestia is miserable.
Personally, Celestia has had few surprises — oh, there were a few: the unexpected return of her dear sister, Discord, the Crystal Empire's, and Tirek's escape. But most things, she finds, are nice and calculated... until now.
Twilight finds an orphaned foal and adopts it as her own, but Celestia knows that this bright young life is not long for this world. She is faced with the dilemma of what to tell her student, but even she cannot know the implications of her decision.
General Sabaton worked under Princess Celestia since the start of the Second Great War. He recalls the time he saw her when she wasn't trying to show any might or bravery for her ponies.
The changelings have been reformed. Many ponies are hesitant to accept them due to their sinister past. Twilight converses with Celestia and Luna about the proper action to take after Chrysalis's defeat. All three are met with differing opinions.
One day, something terrible and unexpected happens to Celestia, and time is lost to the sands. She'll find that her entire world is gone and that almost everything she knew and loved has disappeared...forever.
In this sequel to "Defender of Equestria," a Changeling General goes on trial in Canterlot for numerous war crimes, including kidnapping Cadence and Twilight, while Shining Armor's mentor and predecessor attempts to make amends with Celestia and Luna
A psychotic break leads to a princess under house arrest. During daily tea visitation, Celestia tries to help her sister open up about her troubles. But Luna has a topic of her own to discuss.
Following the Changeling Invasion of Canterlot, Twilight's friends, Princess Celestia and Shining Armor lament over how they failed to protect Canterlot from the Changelings as well for their behavior towards Twilight at the Wedding Rehearsal.