Cloudsdale was in shambles. Buildings and homes were destroyed, ponies were fleeing for their lives, and chaos was reigning in the city. It all looked as though the Mane 6 and Discord had arrived too late to help. Rainbow and Fluttershy looked on in horror at the ruins of their childhood home. The whole city was totally decimated.
"This is terrible…" Applejack said, her expression one of complete shock.
"Anypony who would such a gorgeous city must be pure evil!" Rarity shouted in outrage at the sight.
Twilight was about say something, but stopped herself when she saw Rainbow shaking with what could only be anger. She could easily understand why: she'd feel the same if Canterlot had suffered this fate. But hey had to stay focused on their main goal. "Rainbow," Twilight said to try and get the pegasus's attention.
"I'll beat 'em senseless for this!" Rainbow Dash suddenly shouted. "Nopony messes with my hometown and gets away with it!"
"Rainbow," Twilight said calmly, "I know you must be upset, but we can't let the Aspects get the better of us. We have to keep calm and think rationally about this."
"She has a very valid point," Discord pointed out. "They'll likely try to make it so you six will be too caught up in your emotions to fight back against them. That's what I would've done at least." He walked out in front of the group, examining the damage. "I don't see what you ponies are complaining about. I can fix all this in a snap!"
"Well, then do it!" Rainbow snapped.
Discord recoiled at her attitude a little. He recovered quickly, however, and nodded. "Stand back, ladies!" He clapped his hands together, then stretched them back out, releasing a wave of white light that washed over everything in the entire city of Cloudsdale. When the light vanished, the spirit of chaos took a bow. "Please, please, no need for applause. I know I'm great!"
"Um… D-Discord…" Fluttershy stuttered out. "I'm sorry to say this, but y-you didn't fix anything."
Discord stood straight up, a dumbfounded look on his face. "Wait, what?" He turned to see that the city was still in ruins. "Oookay. That should've worked. Let me try again." He created the flash of light again, only to have the same result. He tried three more times, and nothing. "All right, something's definitely wrong here. Why won't my powers work?"
Out of nowhere, there was a flash of red light, and a single figure appeared from the light. Descending slowly and deliberately was… Twilight Sparkle. She had a slightly different appearance, her mane being completely black and her coat being a darker shade of purple, but otherwise, she was an exact duplicate. No one spoke as she touched down on the clouds. Her expression was completely blank, void of all emotion. Her eyes betrayed a cold, calculating glare. Her gaze soon fell upon Twilight.
"I was beginning to wonder when you would make your appearance," the dark Twilight said in a cold, dispassionate tone.
"Who are you?" Twilight demanded more than asked.
"I am Dusk," the dark alicorn said with frightening calm. "I represent the Aspect of Chaos known as Logic."
"Well, Ah reckon that explains the lack of expression," Applejack stated.
"Oh, why don't you smile?" Pinkie Pie asked.
"Emotions are an illogical hindrance," Dusk replied deliberately. "They are merely an obstacle that keeps all of us from the truth of this world."
"How can you say something like that?" Twilight asked, shocked at her double's emotionlessness.
"The only thing that truly matters to me is making sense of the madness that pervades throughout this universe. The only real truth of this universe is logic. Cold, deliberate logic that sears away meaningless hopes and eliminates infantile dreams."
"Wow," Discord said, completely amazed by Dusk's heartlessness. "I knew she'd be an emotional blank slate, but this is even duller than I originally expected. How boring."
"Discord," Dusk said, finally acknowledging the spirit of chaos. "You would likely be thrilled to know that chaos is returning to Equestria. Does this not please you at all?"
"Normally, it would," Discord admitted, "but I've sort of taken a liking to the ponies here, so I'm afraid I'm going to have to ask you to stop what you're doing here."
"I see." Dusk went silent for several moments, quietly observing the Mane 6 and the spirit of chaos. She then turned and began to walk away.
"Where do you think you're going!?" Rainbow Dash shouted as she began to rush at the doppelganger of Twilight. Dusk's eyes glowed an evil red for a brief moment before Rainbow found herself thrown into a building that collapsed around her.
"Rainbow!" the others called out in shock at what they had just seen.
"My work is done here," Dusk announced. "The seeds of mistrust and anger have been planted. Soon, you shall face the nightmare once again." And with that, she vanished in a flash of red.
Twilight and the others hurried over to where Rainbow had crashed and began clearing the debris. They soon found her covered in scrapes and bruises under the rubble. Thankfully, she didn't seem to have any truly serious injuries. She groaned, letting the others know that she was still conscious.
"Are you all right, Dashie?" Pinkie asked as she helped the pegasus to her feet.
"I'll be fine," Rainbow said with some effort. "Where did that other Twilight go?"
"She's gone now," Twilight answered. "She said something about facing an old nightmare and then just disappeared."
"C-can we go home please?" Fluttershy requested.
"Ya know we can't just let them Aspects have free reign in Equestria, Fluttershy," Applejack pointed out, to which the yellow pegasus tentatively nodded. "Twilight, what do you reckon she meant by that nightmare?"
"I'm not really sure," the young alicorn admitted. She turned to Discord. "Do you have any ideas as to what she meant? You are the spirit of chaos after all."
Discord put his claw to his chin. "Hmm. Well, to be quite frank, I haven't the slightest idea what she was…" He trailed and looked as though a thought had just occurred to him. "Oh. This isn't going to be pretty."
"What? What is it?"
"Think about it. She specifically mentioned 'nightmares.' Who's the one pony commonly associated with nightmares?"
The Mane 6 then thought it over for a few brief moments. Then it hit them like a wrecking ball.
-o-
She woke up to find herself locked in dingy cell in an even dingier dungeon. Where was she? She felt weak, like somepony had sapped her of all her energy. Princess Luna shakily stood up to her hooves and looked around, not seeing anypony, not even a guard outside her cell. She tried charging an attack to blow apart the bars, but found that she couldn't. She struggled again and again, but failed each time. She stopped and began panting heavily. She had never felt this stressed before. What was happening to her?
"Ah see you're finally up," said a voice that had a distinctly southern accent to it. Luna turned to finally see a pony that closely resembled Twilight Sparkle's friend Applejack, but her mane was jet black rather than blond. "'Bout time, too. I wasn't gettin' tired of waitin' at all."
Luna's eyes narrowed suspiciously. "You must be one of the Aspects of Chaos."
"No, I'm not," 'Applejack' obviously lied with a smug grin on her face. "You're not our prisoner either. You're welcome to leave anytime."
"Everything you say is a lie, isn't it?" Luna asked in an annoyed tone.
"No."
"That's enough, Sour," said a voice reminiscent of Twilight Sparkle. Luna's attention fell on the dark alicorn who sauntered into the hall outside the cell with an expressionless look. "You are dismissed. Go and wait with the others. I will prepare our guest."
"I ain't gonna do that," Sour replied as she trotted off to do exactly as she was told, leaving Luna and the dark Twilight alone.
"What is it you want from me?" Luna demanded.
"We want the one who was sealed away for a thousand years," Dusk answered ominously. "You have nothing that we desire. We want the other persona locked within you."
Luna stared at the evil Twilight with confusion before realization finally dawned on her. "N-no! I'll never go back to that!"
"You have no choice in the matter," Dusk replied as her horn began to glow red. "We need Nightmare Moon."
Luna was utterly helpless. She could only futilely resist with all her willpower as she felt the dark alicorn pull her evil half back to the surface. All she heard before being swallowed by darkness was the malevolent laugh of Nightmare Moon.