Twilight finds out her friends are not what they seem...
Gore tag for slight mention of blood. It's so minimal, it probably could go without, but I put it up just to make sure.

Twilight and Celestia talk about alicorns.
That's it.

Twilight Sparkle is teleported and sealed from the Celestial Castle when monsters attack it. She is given six rocks that are supposed to save Equestria, but Twilight doesn't see how six rocks can do that, since they are just that: rocks. However, her mentor recognizes them as the Elements of Harmony, so now Twilight has a new mission: find the Bearers. The first one she runs into is Fluttershy, Element of Kindness. One problem: she is a vampire.
...
Minor details.
Possible TwiShy shipping - you are informed.
"Gore" tag because vampires. Duh.
Comic this is based off of: http://askbattyshy.tumblr.com/page/3

Princess Twilight Sparkle. The Element of Magic, the Princess of Friendship. Her wings and horn signify her as a royal, as an immortal. Her friends, however, are still mortal. Which means they will eventually die. And Twilight will live forever, carrying on the memories of the Elements of Harmony.

Edit 11/11/18: I finally figured out how to add coverart lol

In the far future, after the devastating war with Queen Chrysalis and her changelings, and after Princess Flurry Heart was corrupted by King Sombra and assassinated Princess Twilight Sparkle, Moonlight Sterling, a descendant of Princess Twilight, goes on an adventure to gather the new Element Bearers and bring back the Crystal Empire and reform Princess Flurry, the only living alicorn left in Equestria.

When Princess Celestia discovers a strange portal in a nearby cave, she sends the Mane 6 and Spike to investigate. They turn up in the human world. Takes place after Spike got his wings.

The Mane 6 are having a sleepover, and Twilight suggests they play Truth or Dare. She dares all of them to reveal their deepest, darkest secrets...
It does not go well.

It's Heartswarming Eve, and it's supposed to be the happiest time of the year. Not for the Pies...