After millennia of imprisonment, the chaos spirit Discord has broken free of his stone prison. Celestia wastes no time gathering the Bearers of the Elements, but before she can retrieve the Elements of Harmony, she falls victim to one of Discord's nefarious schemes, no doubt set up many eons ago to exact revenge upon the Princess, designed to make her suffer as he did for so long.

Or maybe he just superglued her horn to a keyhole.

Something is wrong in the World of Dreams. Luna is unable to patrol the dreams of her citizens, and vivid nightmares plague the Elements of Harmony. When Applejack finds that her friends are trapped in their dreams, Luna gives her one task: she must journey into the World of Dreams to bring Twilight and the others back to the waking world.

But if she falls asleep, the nightmares will trap her, too.

Inspired by the Justice League episode also titled "Only a Dream".
Cover image by Raikoh-illust.