The Boy named Tanxhan has to piece together who he is and what happened to his kind when the Equestrians took over Civilization, and he has to befriend them in order to survive. Twilight is a little skeptical about Princess Celestia's faith in these two creatures on this side of the mirror, but she's willing to help them because they hold something big that may decide the fate of Equestria. If Tanxhan can live with these ponies in peace, it will be the start of an age of prosperity. If Twilight cannot help these two adapt to life on the new earth, it will mean death for them all, or so the Creators say.