Over a thousand years ago King Sombra, the tyrannical ruler of the Crystal Empire, was turned to shadow and exiled to the frozen north. Before he could be banished however, he cast a curse on the empire, causing it to vanish.

A thousand years later, the empire returned, bringing with it King Sombra. Using the love and friendship of the crystal ponies, Sombra was banished once more. Sombra isn't the kind of pony who gives up though and, once he learns of the Elements of Harmony, devises a plan that will give him the strength to overthrow Celestia and rule over all of Celestia! He won't be able to do it alone though, and who better to do carry out his plan than his son?