Rain Flare, a member of Princess Luna's Royal Guard, has been reassigned to the border shared by Equestria and the territory of the Changelings in response to their attack at the wedding of Shining Armor and Princess Cadence. Shortly after his reassignment, the bat-winged pegasus is called back to Canterlot by his princess for a special assignment. He could never have guessed what it would be.
Takes place a little while after the end of season two.
Rating subject to change if I feel comfortable.

Thanks to NotTheOP, Exolief, and DeepPond for their critiques! (this thanks is waaayyy over due, I sincerely apologize)