Prophecies
#3 of tales of the dark horse, season 3 action! adventure! space things! coyotes getting themselves involved in interstellar relations! it's some good-natured sci-fi smut, because hey, it's friday :d _action! adventure! space things!
5th Anniversary Director's Cut Special Collector's Edition Extras
After all, it's specifically set right after season 3, which - in addition to ending with twilight's ascension to alicorn-status - also featured discord's reformation and befriending of fluttershy.