A flip of a coin. A twist of fate.

Twilight Sparkle, younger sister of Princess Celestia's personal student, Shining Armor, grew up listening to her brother's bygone dreams of joining the elite of the elite: The Royal Guard.

Now, fresh out of the Academy, this young mare is ready to prove herself equal to the deeds of the great soldiers she read about as a filly. Too bad the princess she ends up protecting isn't Celestia.

Twilight Sparkle left Equestria willingly one day, leaving only a note explaining not to look for her. Her friends did regardless, causing themselves unfathomable pain. After a decade, they had nearly forgotten about her, moving on; one day, however, a mysterious mare enters Celestia's court seeking an audience. Celestia recognizes the mare under the cloak; it was her most faithful student! She had returned, but how have the sands of time changed her? Is she still the book-loving unicorn they once knew? And how will her friends react to her return from the grave?

The description was edited by jamlamin
6/7/14: This story, after reviewing my own work, I deemed a mess and decided to put this on hiatus a few weeks ago. It's not the writing itself but the story, its not constructed that well, my biggest problem being my AU Twilight is just a poorly thought out, she's suppose to be broken yet I basically portrayed her as OP. I may eventually continue this, but most likely If I did I would just rewrite it.

Aiden Aigo, former coder for the the Canterlot City Internal Operating System and the Aitselec Corporation, current pointless rebel, wants nothing more than to get revenge on the company that fired her. One day, Aiden finds something that may be able to help her do just that.

Provided she can get her to work.

When Daring Do's latest adventure goes south, the adventurer finds herself stuck with a regressed Rainbow Dash. Can Twilight fix the curse, or will Rainbow Dash have to grow up all over again? And will Daring find she likes being a mother?
Takes place during season four

Collab between me and Reverse Scratch
Cover art used with permission from Cuddlelamb
Proof read help by SuperPinkBrony12
Not sure if Teen rating needed but never know. .

Equestria had changed. The High Echelon ruled it. It was made up of Discord, Chrysalis and Sombra. The Dark. If there was one thing they were against, it was phoenixes. Nopony knew why. What happens when Twilight Sparkle, finds one in a tree one Winter?

After being lost in time and space for centuries while fused with Discord, Twilight Sparkle has begun to lose her faith in herself and the Elements of Harmony. It is not until an encounter in Manehattan and a deadly fire that she begins to find her purpose again, and search for a way back home.

(Cancelled!)

10 years ago Nightmare Moon returned, Successfully bringing about eternal night. That day Twilight lost everything she held dear. In that time, she has been preparing for the day when she can take Equestria back from her.

Twilight decided to recover the things she lost when Tirek destroyed her house, but what she did not know, whas that it was the begining of a very long journey, and the first step was finding her as a changeling.

Little by little Twilight begin to discover a new reality and begin to question herself about if she was the same Alicorn Princess Twilight at the begin of the journey or Twilight Sparkle, Princess of Changelings

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

Four alicorns to unite the races and protect the kingdom of Equestria. That's how the old legend goes. Years after its creation two sisters are born, one an alicorn and the other a unicorn. One became angry at the other's actions, and ended up sealing the fate for the two with a spell that had unforeseen consequences...

Years later when Celestia is a name all but forgotten to the flames of the sun, Luna is on a desperate hunt for any signs of her sister. Cadence and Flurry Heart have been born while Luna still believes Celestia is the fourth alicorn of the age old story, unbeknownst to her the dark secrets that lie with her sister's wings, and a very important mare hidden in the streets of Canterlot... But nobody's panicking. Right?