Twilight becomes alicorn of the stars. This is sort of a problem, because Luna kind of already was alicorn of the stars. Oops!

TV Tropes

Twilight Sparkle and her fellow Elements of Harmony have faced down supernatural foes of the highest order, but sometimes the deadliest danger can come from places one would least expect. As Twilight is forced to bear a devastating secret, her efforts to keep the Elements together may well tear them all apart.
The plotline of the thrilling Pony Psychology Series continues with an exploration of deception, despair and Discord.
This series takes place between Season Two and Season Three.
Secrets and Lies shares the Pony Psychology Series TVTropes page.

Twilight and Dash, upon discovering that the long awaited "Daring Doo 4" movie contains, eugh, Humans, decide to rent out A Nightmare Moon on Elm Street.

Of course all their friends are invited. There is absolutely no way any shenanigans could possibly ensue.

None.