***Light Dark: For scenes dealing with ponies' fears. Nothing gory or overly traumatizing.***

Celestia receives a letter from Shining Armor and Cadence, asking for her help in destroying an artifact of dark power. Luna volunteers to go to the Empire, and takes along a single pony from both the royal and lunar guards. Their task becomes dangerous, as they discover that the artifact has a sinister intelligence directing its actions. The trio, along with a crystal pony, is pulled into a deadly struggle, not only for their lives, but for the fate of the Crystal Empire.