Twilight, age twelve, has been studying under Princess Celestia for five years. She has learned a lot of things, not just about magic. She spends a lot of time reading books. The subjects range from the history of magic to the history of Equestria. Every topic has a book, sometimes two, and she’s able to get enough details about all of them.

All of them except one, that is.

When it comes to the Griffins, they cease to be mentioned somewhere along the line. From what Twilight is able to piece together, they disappear from history shortly after the formation of Equestria. That doesn’t make much sense to her, so she goes to ask about it from her mentor. If anypony knows about what happened, it would be Celestia.