Shining Armor and Cadence's spell reveals something completely unexpected as it expels Chrysalis and her changelings out of Canterlot: A secret kept from everypony for several years...

Now with a TV Tropes page! Warning: Will Contain spoilers.

There once was a little filly named Diamond Tiara. This is the story of how she died.

...No, that's not quite right. For there was in fact another filly by the same name. Another Diamond Tiara, who lived. She was the second one. It's confusing, I know, but I promise it will all make sense in the end.

It all started on a perfectly ordinary day in Ponyville, when Princess Twilight Sparkle and her friends were trying to stop an insane magic-powered golem from destroying the entire town.

This is the story of two little fillies named Diamond Tiara. The one who died, and the one who lived.

Takes place during season 4, shortly after Twilight Time.