It has long been the subject of dreams; for earth ponies to harness the power of the unicorns' active magic, for the unicorns to leap into the air and feel free as their pegasus bretheren, and for the pegasi to have the immense strength earth ponies are known for.

For some time after Luna was purified from her Nightmare Moon form, she has been experiencing acute amnesia. Memories of her past have been fading from her mind, her happiest memories. Unsure of the cause, Celestia suggests she go visit Komodo University, situated deep in the frozen north. There, the prestigious yet virtually unknown university harbors a deep secret.

They have managed to create hybrid ponies, something Luna attempted over 2000 years ago but ultimately failed to do. They created the arions, earth ponies with a short unicorn horn and the strength to tear craters in the sacred earth; pegacorns, unicorns that were given the power of flight at the cost of their leg muscles being in a state of atrophy; and chollima, pegasi that were blessed with the strength of earth ponies but cursed with the energy of both races.

Curiosity abound, Luna journeys off to see these hybrids for herself. But what she doesn't realize is that they harbor a great secret, one which will lead her into a grand war that nopony knew was even brewing, one which may just lead Equestria into greater chaos that even Discord could dream of.