On The Other Side of the Everfree

In Equestria, a unicorn becomes an alicorn, given wings by her teacher and thus becoming a princess. In a shadowy place, a shadow unicorn also becomes a shadow alicorn.

She flew swiftly over the Everfree, for once not having to worry about the dangers. The purple mare did a few twirls in the air, her purple mane flowing behind her. She shouted in glee, until she ran into something in the air. She kicked her hooves as she fell, something sending the blows back. Twilight and the other thing crashed through the trees, the one being caught in the branches as she struck the ground.

"Ugh..." the other thing moaned, the branches that held it creaking. Twilight stood up and held a hoof to her head before looking up to see what had ran into her. A black alicorn was caught in the branches, looking down at the mare with red eyes.  Its red mane was a mess, but still able to recognize how it looked.

"Aren't you going to help me down?" the mare hissed, the sound of her voice sounding so familiar. Twilight stared in amzement before flying up to help. She used her magic to pull the branches away, letting the shadow pony to fall onto the soft grass.

"Who are you?" Twilight landed in front of the black mare, a confused tone in her voice.

"Chaos Star, may i ask the same to you?"

"Twilight Sparkle."

"Who cares." The mare stood up and hissed before running through the trees. Twilight broke into a sprint as she followed after the dark alicorn. Chaos ran quickly, running past the dark cottage, her terrifying friend, Fear, standing outside with her shadow rabbits. Twilight sped up, finally tackling the alicorn when they reached the center of the town. Both of them rolled before Chaos was on the ground, a purple hoof on her chest.

"Explain to me why you look exactly like me." the purple mare hissed.

"I would like to know the same!" The black alicorn pushed the copy off and flew a few feet off the ground. Five more shadow ponies trotted over. A pegasus with a dark rainbow mane darted up into the air, stomping her hooves against a large thundercloud. Twilight collapsed from the pressure of the rain and sudden boom of thunder. A different pegasus with a dark pink mane laughed as the pony shuddered in fright.

"What are you ponies!" She managed to mutter, a great rush of curiousity covering her fright.

"A dark race, they are Shadow Ponies, and i don't Celestia will be glad to hear that her student found us." A dark blue alicorn standing no larger than the princess of night landed in front of the ponies.

"L-Luna?" Twilight looked up, hope building up inside.

"No, I am the princess Dusk!" The alicorn folded her light blue wings. Her purple mane flowed like the princess of sun, and her mark represented the setting sun.

"W-What?!" Twilight shot up from her spot, all hope fading instantly.

"And you are under arrest for attacking the new Princess Chaos Star!"