After the fall of the changeling hive, Twilight meets a new filly that has seen the Queen's whereabouts. Without wanting to alert the others, Twilight decides to go undercover with her new ally in search of the missing villain.
These two royal alicorns: cunning sun and gullible moon, go about their childish conversations and attitudes whenever nopony is looking-- well, except for a certain Purple alicorn. And you're involved, too.
After a few romantic incidents and subtle attacks from a formidable villain, the Tree of Harmony's friendship map is extended, allowing a certain trio to tap into "unsuitable" areas once deemed to rot and burn under the verdicts of Luna and Celestia.