It's been two and a half years since Twilight Sparkle returned from the other world, leaving Sunset Shimmer in the company of the alternate group of friends she made. However, not all has gone well for her one-time rival in the other world. On the night of the 30th moon, Sunset emerges from the mirror and uses an ancient relic to switch their bodies. Alone in the care of Sunset's overbearing ex-tutor, Twilight uncovers the forgotten past that drove her rival to such desperation, while back in Ponyville, Sunset struggles with Twilight's lifestyle clashing with her own dreams.

Proofreaders: RTStephens, Winter Solstice, The Albinocorn, Dartrunner and NightWolf289.
Cover art: FallingRain22

Featured by Twilight's Library September 2014.
Featured on Equestria Daily

Twilight, Applejack, and Rarity have a sleepover. Certain uncomfortable secrets come to light.

Thanks to Einhander and Exuno for their help.

This story is a sequel to The Art of Rainbow Engineering

Following Twilight Sparkle's explanation of the scientific method, Diamond Tiara asserts that the sonic rainboom is a scientific phenomenon. Scootaloo insists it is magic. The Ponyville schoolhouse is the scene for an unprecedented intellectual dispute.

It's a sonic rainboom. How not scientific could it possibly not be?

A side story to The Art of Rainbow Engineering - you don't need to read that first.

Countless adventures in friendship and harmony have brought the mane 6 to princesshood--all except Rainbow Jennifer Dash, who can't seem to figure out how to earn her place in the world. Aging and weak, with just a few years left, will Rainbow ever become a princess, or will her friends outlive her?

"YOU ARE NOT THE REAL PINKIE PIE!"
"You probably shouldn't even exist."
"You're only a clone, you don't HAVE any feelings!"

Who was she to believe? She was barely a day old, and already she'd seen the disappearance of her mirror images, all but her. Was she just a clone? A disposable unfeeling analog?
What would happen if she became her own pony? If she became real?

Is it possible for one of the Pinkie's, the only copy left behind, to develop? To become an entirely different pony to the one that she was modelled after?

Oh, and before I forget, thanks to the amazing WerewolfNobody for the (At one point) cover art!
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