(Taken place prior to "Wonderbolts Academy")

Skyball is the most popular aerial sport in Equestria and well known around the world. The princesses decide to hold an open tournament, the winning team gets 1,000,000 bits in prize money and a chance to face off against the Wonderbolts themselves in a final game.
Seeing her chance at stardom, Rainbow Dash assembles an unlikely team to play in tournament. Can the Ponyville Pegasi rise to the occasion, or will they be grounded by the competition?

Image source: http://browse.deviantart.com/?q=little+wonderbolt#/d48savw

In a universe full of infinite possibilities, Nightmare Moon has ruled Equestria in Eternal Night for one-thousand years. But when she is shown a vision of a world where ponies live happily in sunlight and where Celestia still holds dominion, she begins to fear for her crown. With the aid of powerful magic and an entire army behind her, she lays siege to the other world.
The tear in the fabric of reality threatens to unleash even more unspeakable horrors, and when Spike goes missing, Twilight Sparkle and the Bearers of Harmony must cross to the world of darkness and find themselves to help close the portal linking the two worlds together.
But in this new world, not everyone is who they seem....

Awesome Image found here: http://huussii.deviantart.com/gallery/?catpath=/&offset=48#/d47936c