Haha, see what I did there?
Warning: spoilers ahead for season 4 episode 19 'For Whom The Sweetie Belle Toils'.
I have to make a journal about this episode because I absolutely loved it, it's definitely one of my favorite ones this season(which for me is saying something because this season has had a lot of great episodes).
In case my (currently running on two years now) 'Trixie Vs. Hearth's Eve' Christmas comics wasn't enough of a clue, I love the classic Charles Dickens story 'A Christmas Carol'.
I adore stories of fallen main characters who through a force outside of their control are shown the errors of their ways.
The slow build-up of moral revelations that lead to that moment when they are hit with the clarity that they are the ones who're wrong all along and they then see the right way to go. That is just pure literary candy for me.
I assumed there would be an episode like this, but of all the characters on MLP who expected it to be about little naive and innocent Sweetie Belle and her relationship with her beloved big sister Rarity(to be honest I expected the fallen character to be Rainbow Dash
Of course there is the Luna part, any episode with heavy amounts of an ancient character(Celestia, Luna, and/or Discord) is going to be an awesome one. Luna being the combination of Marley and the spirits was a cool idea.