Twilight's P.O.V.

Twilight ran up the stairs of the Crystal Palace, tried a gravity reversing spell and slid all the way up. She turned to tell her assistant, Spike, and then remembered that he wasn't here. Panting, she reached the top and saw the Crystal Heart shining on the platform. When she stepped on it, a wall of black Crystals surrounded her and the crystal heart disappeared. "Sombra, enough with your tricks!" Twilight shouted. She tried to teleport out of the barrier, and was successful, if only for a moment. The wall's dark magic thrust her back into the wall and she slammed herself against the wall.

Sombra appeared out of smoke and said, "Well, well, well, it's Twilight Sparkle herself! The faithful student of Princess Celestia. Well see how you can get through THIS one!"He tossed out some black magic and  a door appeared.

Twilight stepped through it and found herself... back in Canterlot?! Princess Celestia was sitting on her throne writing answers to letters she had received about Twilight's failure. "Princess Celestia?" Celestia turned, no kindness in her eyes, or mercy that was showing. "Princess, I don't understand and the door and-"

"Go Twilight Sparkle." Celestia said.

"Go? Go where?" Twilight replied shakily.

"It doesn't matter where. Just away from Canterlot. You are a disgrace!" Celestia spat the last two words at Twilight, making her flinch.

"But, Princess, I don't understand!" Twilight protested.

"YOU FAILED THE TEST, TWILIGHT!" Celestia used the royal canterlot voice, blasting Twilight a good few feet away.

"Princess NO!" Twilight yelled. The princess' horn lit up and a blast of yellow magic brought her back to ponyville, crying on her bed in Golden Oaks. She was trapped in Sombra's door to her darkest fears...

Sombra's P.O.V.

Sombra watched as Twilight's tears started spilling as she saw her worst fear come true. Her sanity was about to crack when Sombra put a hoof on her, seeing her eyes glazed over, turned into smoke and disappeared up Twilight's open mouth. 'what is it you want most?' Sombra though as he searched Twilight's brain. He saw a picture of Twilight being an alicorn and smiled. THIS was what he was looking for. Holding on to Twilight's memories, he escaped and put a 'trance' spell on her. Her eyes started closing and she fainted, her eyes fluttering closed. He worked his magic on her, producing a pair of lavender wings that matched Twilight's color. He opened her eyes slightly and saw the red and green pupils flowing with light purple contrails. He smirked and told her to get up. She got up immediately and his spirit was sucked into Twilight's body. Inside she explored her thoughts.There were 'Celestia doesn't want me.' and 'No, that's no true!' Her mind seemed to be having a battle between her dark sides and her light sides. The dark side was apparently winning as Sombra saw more and more of the dark and brooding thoughts appear. Finally darkness had won, except for one super-bright good though which was, 'MY FRIENDS WON'T ABANDON ME!!!" Sombra growled and put a fear spell on the though, causing it to tremble and change to a dark thought. Sombra escaped and saw Twilight's eyes narrow with anger. He took off the spells she put on her and her eyes began to be angry, leaving no trace of dark purple left. As she stood up, Twilight said, "Celestia doesn't want me." Twilight turned to Sombra and said, "I want you to be my teacher, Sombra." Sombra, surprised by this proposal, said, "Of course Eclipse Shadow." And with that, student and teacher walked into the shadows of the corrupted Crystal Palace.