Okay, finally an episode that actually caught my interest. Misty follows a flying magic book and stumbles into a secret room inside the Brighthouse, but her main concern is making the door out of the room reappear so she can escape. She eventually succeeds (though not without a few mishaps) after she realizes the book she followed is a magic spell book that'll teach her all kinds of magic spells, with the first such spell she learns being how to make the door appear whenever she wants to visit the secret room again. This is very significant for G5, as virtually all unicorns have done little more with their magic than basic levitation, with none of the complex spells we remember from G4's unicorns, so this really opens the door (no pun intended) to possibly seeing these G5 unicorns relearn some of those lost spells, with Misty being the one to rediscover them and possibly even share some of those spells with her fellow unicorns. In addition, it was hard to miss the stained glass windows in the secret room depicting the G4 ponies, and unless I'm mistaken, this might be the first time ever in TYT that any direct reference to G4 has been made, albeit as merely background images. Even so, this episode had its lesser moments in my opinion, such as that spell book just spontaneously show up at the beginning, along with Misty reciting her power-up call-out to cast her spell to escape the secret room. Overall, easily my favorite episode of Season 2 thus far, though that's honestly not saying much.