This story is a sequel to You Call That A Costume?

When Pinkie Pie is in charge of the Independence Day fireworks celebration, she decides to add her own touch with her specialty fireworks. Intrigued, Sunset and Twilight decide to get involved to help take it up a notch. Naturally, hilarity ensues.

When Twilight Sparkle was just a kid, her best friend was a girl named Sunset Shimmer. Though their friendship had a bit of a rocky start, they quickly became inseparable, no matter how much everyone thought of them as ‘weird’. They were there for each other.

Were.

Years after the tragic accident that tore them apart, Twilight is determined to move on from her loss, and she sets off on an independent research project to investigate the strange happenings at Canterlot High. Little does she know that she will soon come face to face with what appears to be a literal ghost from her past.

Coverart by Kare-Valgon. Chapter illustrations by Zorbitas.

Edited and Pre-read by Dubs Rewatcher, r5h, and Kalan.

Takes place after Rainbow Rocks, but was written before Friendship Games and does not take it into account.

Chinese translation

Print copies now available.

Sunset Shimmer has a crush on Twilight but knew she couldn't love her because Twilight is in a happy relationship with Timber Spruce. When she heard that Timber got into an accident, she quickly rushes to the hospital and the doctor told her that he needs an A+ blood and a heart. Sunset immediately volunteers because she remembered how Twilight looks sad and was crying because of what had happened to her boyfriend. So she sacrifices her own life.... for Twilight to smile again.

Canterlot High School is having a talent show, and the Rainbooms are eager to join in. However, things get complicated when the human world version of Sunset Shimmer suddenly makes an appearance. After much confusion and several mix-ups, she finally meets her counterpart and her friends. Unlike her counterpart, however, she's shy and reserved. The girls try to befriend her, but this Sunset doesn't seem to be too interested in friendship. She is, however, very interested in the rumors of magic surrounding Canterlot High, and seems to be hiding something magic related herself. And when magical mishaps begin to occur, the Equestria Girls begin to suspect that this new Sunset may be behind them. Is it possible that she's evil and power hungry the way her counterpart once was, or is there something else at work?
STORY COMPLETE

In "A Canterlot Wedding", Twilight just wanted to protect her brother from the Cadance imposter who was Queen Chrysalis. However, he didn't believe her and was subsequently barred from the wedding; this left a heartbroken mare in his wake. Enter BLANK, a Changeling who seems to mean both good and bad.

BLANK manipulates Twilight into reaching a bargain: if she helps him get his revenge on Princess Celestia, he will help her get her revenge on Queen Chrysalis. Twilight agrees, unaware of the madness behind the mask of a charming Changeling, who seems to develop an interest in the young mare as well.

Several years had passed after Tirek's defeat and everypony is preparing for this year's Summer Sun Celebration. But Twilight is not feeling well. Several nightmares are haunting her, she has got bad headaches and a really mad mood. Although Spike and the others tell her to go and fetch help, she refuses. But when some dark incidents and curses happen, Twilight realices too late, they had walked into a trap and it has snapped behind them. For the foe is inside of her and preparing her last and final strike. To turn the celebration into a true nightmare.

Canterlot has been liberated after the changeling invasion, but Twilight cannot let go of the heartache from being disowned by her brother.

Twilight is now gone, her friends and family are devastated. Twilight must now have to find a way back. She has to. Doesn't she?

Special Thanks:
Thanks to Stormy Venture for all the help!
Thanks to The Myth for the plot!

I stood there silently, looking deep into the eyes of each and every one of them. I wouldn't leave until I had what I wanted.
"Well?" I asked, growing impatient. "Do we have a deal?"
One stallion stepped out of the shadows, "Oh, we have a deal all right." he stated.
I grinned at him.
"But," he added, "Only because we know what you are."
"Oh?" I asked, my grin turning to a smirk. "What am I?"
He looked at me coldly.
"Poison."

The following description is guaranteed to at least a little change with time. I'm kinda writing the story as I go. But here's a basic description to go by.

Poison is a young mare who, because of trials as a foal, has become an assassin unmatched in skill. She was born into the badlands outside of Equestria's harmonic reach, and into an evil monarchy government.

The evil dictator running it all is known for taking every precaution against all threats. Those who escape his wrath are few, those who escape his kingdom are fewer.

And those who survive opposing him are almost non-existent.

The experiences and horrors she endured after being taken from her home have taught Poison one thing; never give up. She was originally taken as another foal he could use in his ever powerful army. But ever since she escaped, every waking moment is spent seeking out ponies within the monarchy to take down.

One day, she discovers he has plans for their neighboring country of Equestria. Plans that include releasing every demon in Tartarus upon them, leaving him to rule over the remains. With the danger of this new threat, as well as the fact that Equestria is completely unaware, Poison makes the decision that it's finally time to join forces with the resistance.

She offers her services, which they gladly accept thanks to her reputation. She is given a team of elite fighters and spy's who, combined with her skills in assassination and keeping undetected, make an invincible force. They will be the key in taking down the monarchy, and keeping the demons in Tartarus where they belong.

Poison, along with her new team, strive to end the evil monarchy once and for all.

Nothing will stand in the way of her completing her mission.

Even if it kills her.

(I'll probably include the CMC in here somewhere because it AU. Not quite sure where yet.)

Twilight Sparkle: perfect student, lives in Ponyville, has great friends, and the newest princess of Equestria. That was her life before the tragic event happened.
She is transported to a new universe where she never met her friends and lived alone in darkness. Alone in a new universe with some memory problems, Twilight must find out who she is, before losing herself entirely.
...
Life in Equestria was perfect for Rainbow Dash. Her mentor, Princess Celestia, has given her a lovely home in a town called Ponyville. She and her friends helped keep harmony in Equestria by restoring Princess Luna to her rightful place as princess of the night.
There have been no problems in town, until a strange alicorn appears and claims to have no memory of anything but her name before appearing.
Rainbow, along with a strange stallion named Blue, wish to help her, but how can she help somepony who doesn't even know who they are themselves?