Back in the hallway Pinkie Pie, Sunset Shimmer, Twilight Sparkle, and Spike were still picking themselves up off the ground.
"Ughhh..." Sunset Shimmer moaned as she lifted herself to her feet. "That just happened, didn't it?" She glanced over at Twilight Sparkle, who was wiping off her glasses. Twilight responded with a nervous nod as she put her glasses back onto her face.
"The last time that happened..." Pinkie Pie started to say.
"...was when Princess Twilight Sparkle was here," Twilight finished for Pinkie. She picked up Spike off the ground, who gave her a lick on her cheek.
"I thought you said that this could only happen if the dimensional double had tapped into their magical potential," Sunset reminded Twilight. "How could she if she hadn't come into contact with any of us until now?"
"I guess I was wrong," Twilight said, disappointed her theory was incorrect. "I suppose all creatures carry magical energy even if they've never been exposed to Equestrian magic. We were just never able to see it in our world until it was brought through the portal." Sunset frowned at Twilight's postulation.
"So BOTH Sunset Shimmers go to Canterlot High?" Pinkie said, seemingly enchanted by the fact that such an unlikely coincidence had occurred. The two other girls looked at her incredulously, mildly bewildered by her upbeat assessment when the reality was clearly much less optimistic. Pinkie Pie shrugged in response. "What do you want me to say, it's still kind of cool when you think about it."
"It won't be so cool when she finds me again and rips reality apart just by making contact..." Sunset Shimmer reminded her with ominous dread in her voice.
"She stole my notes and knew what I had been researching," Twilight explained. "She figured out that you were a duplicate from a different dimension and was trying to get me to explain the meaning of my notes to her before you and Pinkie Pie showed up. But now that she saw for herself what can happen, she won't need me anymore, just you..."
"So she was already aware that I wasn't the same as everyone else at this school, even before she knew exactly how we were connected," Sunset deduced. "She won't back down knowing that she and I are linked together and that she can use me to discover whatever magical potential she has, even if she doesn't actually know what she's stumbled on."
"I wonder why she's so interested in magic," Pinkie thought out loud. "It's not like any of us had ever talked to people about what happened at the school."
"Well I was able to figure out something wasn't normal about this school," Twilight said, reminding her friends of what drew her to Canterlot High in the first place. "It's not a stretch that she may have found out through some other means."
"Regardless, it's not safe for me to stay here at Canterlot High. I have to open the portal and return to Equestria before I run into the other Sunset Shimmer again," Sunset told her friends. "Call the others and tell them to meet me at my locker."
Rarity, Fluttershy, Rainbow Dash, and Applejack arrived at Sunset Shimmer's locker as a group, where they found Twilight Sparkle with Spike and Pinkie Pie waiting with her. Sunset had her head in her locker and was writing something out of view from the others.
"We got Pinkie Pie's text and came as quick as we could, what's the trouble, Sunset?" Applejack asked, concerned over the urgency of the message.
Sunset came out of her locker with her magic journal in hand. She was applying the final words to her message to Princess Twilight Sparkle before closing the book and returning it to the locker. She leaned against the wall of lockers and slowly closed the door to her own before letting out a long sigh.
"We've...got an unlikely problem," Sunset began. "It seems that, through some strange coincidence, the Sunset Shimmer of this universe...attends Canterlot High." Twilight held up the wig and glasses the human Sunset Shimmer was using to disguise herself as 'Amber Sunrise'. "She was pretending to be someone else at the school, which is why we never noticed."
The other girls looked at each other in surprise. "What's worse, she knows about what happens when two dimensional counterparts come into contact," Twilight picked up the explanation. "She bumped into Sunset and they touched, resulting in another inter-dimensional nexus."
"Now she's cooked up this crazy scheme to make it happen again because she thinks it's gonna give her magic powers!" Pinkie exclaimed to conclude the explanation.
"I was writing a message to Princess Twilight telling her to reopen the portal so I can return to Equestria before I have another encounter with the Sunset Shimmer of your universe," Sunset told the rest of her friends.
"Where did she go after you ran into each other?" Fluttershy asked.
"She took off with Pearlesecent and Jade Jewel," Sunset said. "They were in the middle of interrogating Twilight on what she knew about the dimensional rift and where our Equestrian powers come from when I came along."
"Those jerks!" Rainbow Dash cut in. "They were in on it? When I find them I'll..." She cracked her knuckles in anger.
"No, don't," Sunset calmed her down. "I don't think Jade and Pearlescent knew what Sunset was planning. They seemed just as confused as the rest of us when they got caught up in it."
"But it's not like Sunset knows about magic in this world either, does she?" Rarity asked.
"Even if she doesn't, she's convinced herself that coming into contact with our Sunset Shimmer will grant her the same powers we have," Twilight said. "I don't know why she's so obsessed with having powers but there's probably no talking her out of it."
"And...because of that...I can't stay here..." Sunset said with sadness in her voice. She turned away from her friends and put her face in her arms against the wall of lockers. The others could hear her sobbing before she suddenly pounded the lockers with her fist, rattling all of them. The loud noise caused everyone to jump.
"Sunset..." Fluttershy tried to reach in to make her friend feel better.
"It's...it's not fair to you," Sunset said, still sobbing. She sniffed before continuing. "I wanted to stay at CHS until graduation and...and now this happens!" She slowly slid down the lockers until she was in a crouching position. She turned around while remaining crouched as the rest of her friends gathered around and moved down to her level.
"Where I come from...magic is a controlled element," Sunset explained to her friends. "It's a constant presence in Equestria and everypony lives in almost oblivious harmony with it. When I came here I wanted to use it to control and dominate this world. However I only discovered that...in this world, magic is unpredictable. It's...unstable and random. I brought magic here and it's caused nothing but trouble ever since." She sighed again. "I know I was talking about going back to Equestria but...I didn't want it to be like this! Not because I have no way of understanding of magic here!"
"We understand, sugar," Applejack said, trying to reassure her friend. "None of us could have ever predicted this would happen."
"Did...did I ever tell you how I came to this world originally?" Sunset asked the others. The rest of the girls shook their heads. "Back when I was living in Equestria, I was a rebellious and arrogant unicorn..." Sunset began.
Sunset Shimmer stared out into the dark night sky through the window of her private dorm room within Canterlot Castle. She had been caught breaking into the Spell Archive and violated the trust of her mentor Princess Celestia. On the floor were boxes of her personal belongings that once decorated her room.
"I'm sorry, Sunset Shimmer, but you have gravely disappointed me on this day. If I had allowed you to visit the Spell Archive, you would not have had to break in and so I cannot trust that you will honor my teachings and methods. It is with a heavy heart that I must expel you from private study. Please clear out your dorm room tonight." Her mentor's words still rang fresh through her mind.
Stupid, Celestia, she thought. What use is a mentor who does nothing but hold you back?
Sunset got off her bed, strapped on her saddle bag, and began to roam the halls of Celestia's castle.
"What's the point of staying in Canterlot?" she said to herself. "There's an infinite number of possibilities out there. I can't just live under Celestia's hoof if I want to reach my potential."
She found herself trotting past Celestia's throne room as she wandered the quiet halls. Sunset looked at the empty throne with contempt before slowly walking over and seating herself upon it.
"I, Queen Shimmer," she said, mocking Celestia's regal tone, "hereby banish Celestia of Equestria for being a lousy mentor!" She waved her hoof dismissively to the empty throne room before quietly giggling to herself.
Just then, she heard some sounds coming from the small room adjacent to the throne room. Sunset quickly ducked behind the throne to avoid being found out. As she did, the door opened and Princess Celestia trotted out from it accompanied by a counselor. Sunset Shimmer listened in on their conversation.
"This is the third day of the thirty moon cycle." Celestia said. "Soon the portal will be closed again."
"Why have we not sent anyone through the portal?" the aide asked. "We have observed this behavior for decades but never acted on it."
"I am simply not ready to risk the lives of my people for such a meaningless gamble," Celestia responded. "I cannot prioritize endeavor with the risk that they may never come back from the other side."
Waiting until Celestia and her aide were a fair distance away, Sunset Shimmer walked slowly and quietly around the back of the throne room and over to the door that Celestia had left slightly ajar. She gingerly pulled it open and looked inside. From within, she could see a strange glow emanating from the back of the room. The glow was pulsating and seemed to be centered on the large floor mirror that was positioned at the rear of the storage room. Sunset pulled the door open further and stepped inside. She approached the mirror hesitantly. As she walked closer, wisps of magical energy began to flow out from the mirror, almost as though there was a light breeze that was being produced by the strange mirror.
Back outside, Celestia looked behind her and noticed the door was open. "I don't remember leaving the door open that wide..." She began to walk back to the side room. As Celestia approached the door, Sunset was holding her hoof towards the mirror. Upon touching what should have been the glass surface of the mirror, her hoof phased through.
What's going on...? Sunset thought. She quickly pulled her hoof back out of the mirror.
"Sunset Shimmer!" Celestia said from behind Sunset. Sunset whipped around and saw her mentor standing behind her. "What are you doing here?! Do not go near that portal!"
Sunset grimaced, her mind racing having been caught in the moment. She looked back and forth between Celestia and the portal. "I...I don't care! I won't be lectured by you any more!" she spat, disregarding any doubt in her mind about what she was about to do. "If it means I don't have to live under your methods any longer then that's good enough! Goodbye, Princess!" With that, Sunset broke for the portal and jumped into the mirror, vanishing into the mysterious beyond.
"No!" Celestia shouted. She tried to run after Sunset but as soon as she reached the mirror portal, a great flash of light poured from the mirror portal followed by a haunting silence. Celestia slowly trotted over to the mirror and touched it with her hoof. The portal had closed and the mirror was once again solid. She looked at her own reflection in the mirror before bowing her head and letting out a low, dejected sigh as a single tear rolled down her cheek.
Meanwhile, in the grip of the portal, Sunset was being pulled along by an ethereal force. She had never felt a sensation like it before, as though she was slowly falling apart at a molecular level. Rays of otherworldly light blazed past her at an amazing speed before it suddenly ground to a halt and Sunset found herself regaining consciousness in an unknown location.
"Uhhh..." Sunset Shimmer groaned. She was lying on the ground, her eyes closed, and feeling confused. She tried to move her foreleg but was struck with an odd sensation, as though her joints weren't in the same place as before. She blinked her eyes several times to clear them and looked down to see why she felt so different. Looking at where her leg was supposed to be, she was perplexed to see it no longer resembled a leg, but instead her hoof had been replaced by a strange appendage with smaller limbs coming off the end. Still dazed, she glanced upwards and was greeted with the facade of a large, multi-storied building that wrapped around on both sides of the courtyard. Sunset peered over her shoulder and saw that the portal had brought her to rest in front of a large statue of a stallion.
"What...is this place...?" she muttered.
"...and that's how I ended up here..." Sunset finished her story. "All because I refused to face the consequences for my actions and ran away from my problems. I wasn't any better when I came to this world, I hadn't changed who I was, so I plotted to grow stronger while I was here and someday return to Equestria to defeat Celestia once the portal reopened. I learned the ways of this world and manipulated the students of CHS in order to leverage authority here."
She paused looked around at the other girls, remembering what she had done to them. "I saw any friendship as a threat to my desire for dominance so I lied and spread ugly rumors to divide friends and seed conflict. I played with Flash Sentry's feelings and tricked him into dating me just to share his spotlight...he saw through me but I didn't learn anything. It wasn't until Princess Twilight came here that I...finally realized I was in the wrong. That true friendship is not something to be feared but embraced and selfishness only leads to misery. And now...this stupid circumstance is going to render everything pointless!" She closed her eyes and began to tear up again. "After everything we've been through together as friends, it only takes some bitter girl who doesn't know what she's messing with that's threatening to break us apart..."
The other girls looked on with empathy at their friend's distress. "No one blames you, Sunset," Fluttershy said on behalf of the group. The others nodded in agreement.
"There was no way to know that the...'other you' would be at CHS," Rarity said, continuing Fluttershy's point. "We just had an unlucky break, that's all."
"Whatever happens, Sunset, you'll always have us with you!" Rainbow Dash chimed in. "Friendship isn't something that stops just because you're in another dimension!" She wrapped her arm around her friend's shoulders.
"Thanks, guys," Sunset responded, wiping her eyes. "If I have to leave, I won't forget everything I learned in this world."
The seven girls all shared a big group hug around Sunset Shimmer.
Elsewhere, a classroom door slowly swung open and a lone girl walked through.
"Mr. Clay?" she said, softly. At the front of the classroom, a teacher was working with his back to the door. He turned around at the sound of his name.
"Amber Sunrise?" he asked, when he saw the girl. "What brings you by?"
"I needed to email something to a partner," 'Amber' said. She produced a small removable storage drive from her hooded sweatshirt. "My Internet's in and out at the house right now, they're working on the wires in the neighborhood."
"Sure," he replied. "The computer's already logged in." He pointed towards to the computer on his desk.
'Amber Sunrise' sat down at the desk and opened the email client. She inserted the drive into the face of the computer and then composed a new email. She typed an 'S' in the "To..." field and a dropdown list of names appeared. She scrolled through the list until she saw what she was looking for: "Sunset Shimmer". She grinned slightly then began composing the email. After typing it up, she clicked "Send" then went into the "Sent Items" folder and deleted the email she created in order to cover her tracks. She pulled out her drive and stood up.
"All done, thank you, Mr. Clay..." she said as she left. She exited the classroom with a sinister smile on her face.