Possessed by a question, Twilight sets out to have it answered. Of course, she will have to violate a huge pony taboo to do so. But hay, it's for science!
After an accident, Rarity and Twilight are thrown in a race against time to stop their transformation into changelings before they become part of Chrysalis' swarm forever.
A murder in the mirror world brings Sunset Shimmer back to Equestria, with her world's Twilight Sparkle in tow. While they track the killer, they struggle to reconcile the differences between them and their mirror counterparts.
A strange artifact arrives at Twilight's library and turns her into a dragon. From there, everypony she touches suffers a similar fate and the race is on to find a cure before all of Equestria falls prey!
Lyra and Bon Bon's adoptive son sells a drink that's insanely popular. Apple Bloom thinks he's brainwashing ponies with poison. And it's not just because he's a changeling.