Starlight writes her final farewell to Twilight. She didn't expect this to be this hard. But it's for the best. She only hopes Twilight sees it this way too.
The book was Twilight Sparkle's greatest creation – ask it any question about how your life might have been and see the answer. It is a work of genius. It is a tempting, insightful, wonderful marvel of magic. It is a terrible mistake.
As an orca pony swims one night among the fiery monuments of a global conflict, she finds a sailor freezing to death in the arctic cold. She has only one question for him.
Everypony knows Princess Celestia can't possibly have a dark side. Sunset Shimmer is about to find out just how wrong everypony is, and in so doing, find that Celestia understands Sunset more than she ever thought possible.