"Sorry it has to be this way, Princess."
Celestia's jaw dropped as Sunset uttered those words, so strange and out of context. She immediately reached out her senses to see what could be behind them, sensing the fully charged unicorn at the same time as he stepped into the cavern. She barely had time to start weaving a shield spell before his attack struck her squarely, knocking her back and sending her rolling across the floor. She felt magical bonds wrap tightly around her body and cut off connection to her own horn, draining the charge that she had begun to build. Her breath left her and she allowed darkness to take her.
When her eyes opened again, she gauged that it could only have been half a minute or so. She cast her eyes around briefly, and then snapped to full attention. Sunset was surging on some spell that connected her to the unknown unicorn and she spotted something that made her blood run cold – the spell was focused on the Alicorn Amulet strapped around the other unicorn's neck.
"No," she whimpered, dismayed at her inability to put any strength behind her words. "Sunset... don't!"
But Sunset either couldn't hear her or didn't heed the warning. Celestia's world went white as she was struck by a powerful blast of magic. Instead of pushing her back, she felt this one flood into her body and start to fill her with energy and strength. It was like when she had that first sip of water after ten years, except now she was taking in her first drink of raw magic, replenishing her long-drained stock.
She sat more upright as the flow continued and her magic reserve continued to swell, the white-hot searing of a magical surge starting to leak from her eyes. She was not sure whether she was unable or unwilling to interrupt the spell, but all concern melted away as she gave herself to it. She felt her body start to grow as the magic continued to fill her, the swelling blasting away the binding spell. She could feel her wounds close and bones knit, and she felt compelled to stand and spread her wings. All pain was gone as the fabric bindings were shredded and fell away.
She closed her eyes again as she was lifted into the air by the raw energy, and the magic filled her every muscle. She even felt her mane lift up and begin to flow once again, more magic flowing along every strand. She felt magnificent, she felt powerful, and she felt better than she had ever felt in her life. She arched her body as the flow continued into her breast, only reluctantly taking control again when she felt it finally taper off. She gently lowered herself to the floor and stood there, her head raised as she enjoyed the feeling of being whole again – of being more than whole.
For a moment, all was quiet in the room. But a voice spoke to her in a gentle and comforting tone from somewhere deep in her mind. "That was just what we needed, wasn't it?"
"Yes," replied Celestia.
"Princess?" It took her a moment to realize this voice was coming from the room. She soon recognized the voice – it was her prize student, after all. Her student who had healed her and recharged her own magic faster than any of the uncertain plans she had been trying to develop herself.
Celestia smiled and lowered her head. "Thank you, Sunset Shimmer," she said warmly.
Her eyes opened and she felt this new magic surge again, flowing from her eyes and blasting through her mane and tail. It felt amazing and she marveled that she had never felt so strong before. She saw Sunset standing across the cave looking over at her with her jaw hanging open.
"You have made things so much easier," she continued. She looked up at the ceiling for a moment and gathered power to her horn. A simple discharge of the magic and she blasted a hole clear through to the outdoors. She crouched and leapt into the air, giving her wings a strong flap and blasting through to the outdoors.
The cool night air struck her and she took in a deep breath, looking around.
"This was the only way," suggested the voice. "Without the sun none of the plans to recharge our magic would have worked."
"I know," replied Celestia. She turned her head up to the moon. "Luna..."
"Luna's tantrum has lasted long enough," noted the voice. "It will be easy enough to end this now."
"Yes," replied Celestia, sighing a little. "But I wish I didn't have to."
"She's had time enough to come around on her own. She's hurting ponies. She's hurt YOU."
Celestia flapped her wings, starting to glide towards the castle. "Yes... with her 'Nightmare Moon'."
"You needn't fear the Nightmare any longer... it's time to wake her up."
Celestia clenched her jaw. "Yes... yes it's time. But we... we won't harm her..."
"Of course not... not Luna. But Nightmare Moon…"
"… must be destroyed," finished Celestia.
Celestia looked ahead... by air it was not that far to the castle. She reached out her senses and felt around the bubble shell protecting the tower. Several pings notified her of air patrols around the tower and she considered her plan.
"Straight in, hard and fast, so she doesn't have time to prepare, and those pegasi can't interfere."
She smiled and nodded, "Yes," she replied. "Yes, that will work."
She focused her magic and formed a spike of swirling plasma before her and set it spinning slowly, then gathered a sphere of magic behind herself.
She marveled to herself. "It has never been so easy to gather and manipulate so much power before."
"That's what I'm for," noted the voice.
Celestia released the magical charge and blasted forward with so much speed that flames spread out around her body, the plasma spike spiraling before her and spreading wide around her body. It was only a couple of seconds before she struck the magical shield and she felt the other magic shatter as though it were made of porcelain. She slammed onto the balcony with all four hooves at once, spraying rock chips in all directions.
There was an instantaneous response from the shadows inside the castle as a bright cyan beam blasted out towards her. Time seemed to slow for her and she was able to watch the beam streaming through the air towards her. She stretched out her wings and flapped once, leaping into the air just high enough to clear it. A quick twist of her wings propelled her forward even as the beam was striking the railing of the balcony behind her, and then she cast her senses forward into the dark.
She instantly recognized the signature of her younger sister, and the amplified magic she still carried. For a moment the recognition triggered fear – Nightmare Moon was just before her. Voices came to her from her memories and her nightmares.
"Luna, I will NOT fight you..."
"Luna? I am Nightmare Moon!"
The sound of her own scream echoed in her mind as she remembered being struck, but then the calming voice spoke out in warning.
"Move aside..."
Celestia blinked and looked to see another beam heading for her. She flapped her wings and darted sideways, the beam passing harmlessly along her flank. Without thinking about it she lowered her own head, and then she fired a powerful orange beam into the shadows to where she felt Nightmare Moon was standing.
For Celestia it felt like several seconds, but she knew it was but a fraction of one before she felt her attack strike the wall. Nightmare Moon had faded into mist and spread herself along the walls, traveling nearly transparently around the room. Even with her enhanced senses Celestia had trouble tracking her.
"You shouldn't have come back, sister."
Celestia shuddered as the voice from her nightmares filled her mind, but then her own calming voice replied to her.
"Focus," it said, and Celestia turned her head slowly, trying to track the smoke. She almost had it when there was another blast from the shadows, and she leapt to avoid it. There was another blast as she landed, and she stumbled ducking underneath it.
"Luna, enough!" she cried out, but there was only laughter in response.
"Luna?" asked Nightmare Moon. Celestia's blood froze, and she mouthed the words from her nightmares at the same time as they were spoken. "I am Nightmare Moon!"
It seemed as though the walls erupted in brilliant cyan magic which converged on Celestia's form. She screamed as she felt the burn of the magic striking her, every part of her every bad dream come true. But in the middle of it, the calming voice spoke through.
"Focus!" the voice reiterated.
Celestia looked up with wide eyes as the burning beam narrowed upon her, and before her eyes the mist congregated and solidified into the form of Nightmare Moon. Nightmare Moon glared as her attack continued unabated, a solid beam of burning magic from her horn straight into Celestia's breast.
"Why did you come back?" she demanded, advancing slowly. "I don't want you to be here!"
Celestia watched her advancing, feeling the burn of Nightmare's attack. She shrank back, but the voice in her head chided her again. "She's not hurting us. We are stronger than she is."
"Luna… stop," whispered Celestia.
Nightmare Moon kept advancing. Her pupils were tiny and her eyes wide. "Why are you making me do this?"
Celestia's voice was stronger this time, and she was able to lift her head to face Nightmare Moon. "Luna," she repeated. "Stop!"
Nightmare Moon was only a few paces away now, and her voice was even louder. "Why didn't you stay in the sun?"
Celestia stood slowly as she spoke, her teeth gritting together. "Luna," she repeated. "I said… STOP!"
With the last word Celestia spread her wings wide and her magic surged. She blasted plasma from every pore of her body, erupting in a brilliant nova that filled the room with flame and pressure. Nightmare Moon was blown backwards and slammed against the wall, a clanging thud echoing through the flames as her armor-clad body slammed to the ground.
The room was silent for a moment and then Celestia stepped forward. The orange glow from her mane and tail lit the room with a dim, shifting light, but she was able to see Nightmare Moon up against the wall. The younger alicorn was moving stiffly but with urgency as she tried to sit up.
"You see?" noted the voice. "No longer anything to fear..."
Celestia smiled. "Relax," she advised. "I only wish to talk to you..."
Nightmare Moon's eyes were wide as she met Celestia's gaze and her pupils had reduced to mere pinpricks. "No!" she shrieked. "Stay back!" She shuffled backwards against the scorched stone as she got her hooves underneath herself.
Celestia shook her head. "Look at you," she said. "Nightmare Moon." Her tone was mocking as she stepped forward. "To think how frightened I was of you..."
"What... what have you done to yourself, sister?" asked Nightmare in a small voice.
"No less than you did to yourself," growled Celestia. "You don't like it, do you?"
Celestia didn't wait for a response. "No, you don't like to listen to lectures either, I remember that well enough. But you will listen to this one. You've had quite a little tantrum, haven't you? Gone off and made everypony suffer, just like you wanted to. Are they happy now? Are you happy now?"
Celestia paused, looking at Nightmare Moon half laying, half sitting on the floor. She was watching Celestia with her eyes still wide, her hooves tucked up underneath her and her ears flat against her skull. "She's scared," thought Celestia.
"She needs to be scared," advised the voice.
"But she's my sister..."
"Nightmare Moon put an end to your sister a thousand years ago."
Celestia frowned.
"That was why you never looked for her. Because she was gone."
Celestia thought back. "But, I meant to."
"You knew it was for naught, and now Nightmare Moon has hurt every pony in Equestria."
Celestia's frown deepened.
"She won't stop. You can't let it go. This time you MUST take action."
"What do you have to say for yourself?" asked Celestia.
"S... sister, please!"
"How many ponies have you hurt?"
"It wasn't like that! I mean... I didn't mean to!"
"How many, Nightmare Moon?" Celestia's voice was growing more impatient.
"I... I don't know. I didn't count... I… things are better now!"
"She didn't even care. Nightmare Moon could never care."
Celestia's teeth clenched together as the voice continued. "She caused all of this. She is how you lost your sister and why you were banished. In your absence she has only brought pain to the ponies of Equestria. You swore to protect them – you have to make this right. Nightmare Moon will forever be a threat."
Nightmare started to stand as Celestia paused. "Maybe... maybe enough time has passed," she said. "I... I had grown weary of ruling alone..."
"Nightmare Moon bargains for your mercy, the last ploy of the dictator. After what she did to Luna, she has the nerve to beg for her position..."
"Nightmare Moon..." began Celestia, her voice nearly cracking with anger.
"Sister, listen..." interrupted Nightmare Moon, but Celestia cut her off.
"My sister's name was LUNA!" she shouted. Nightmare Moon cringed back, cowed.
"But... I am..." she whimpered.
"As I was saying," interjected Celestia strongly. "Nightmare Moon: as Princess of Equestria, I hereby charge you with treason, with bringing harm to every pony in this land, with falsely declaring yourself ruler, with too many crimes to enumerate here. How do you plead?"
Nightmare looked into Celestia's eyes, but all she could see there was the flame that leaked with her magic. Seeing nothing she recognized there, at last she relented. She turned her gaze away and lowered her head. "So it's to be the moon again?" she asked morosely.
Celestia smiled, "Oh no... You would only return in another thousand years, and do it all again. But don't worry; my student came up with a little spell that will do nicely..."
Nightmare looked up, a mixture of concern and curiosity on her face, but she did not reply. Celestia nodded once.
"So be it," she said, planting her hooves. She lifted her head and lit her horn, gathering magic to it rapidly. Having been a part of Sunset's spell, she had gained more than enough knowledge to combine with her experience and re-cast it. The glow around her horn intensified as her eyes brightened. When she spoke, her voice reverberated and seemed to fill the room. To Celestia's ears, it sounded as though her own voice mixed with the strangely calming voice that had been advising her.
"Let justice be served," it said, and Celestia spoke along with it. Her head dipped and her magic streaked out to Nightmare Moon, striking her squarely and quickly surrounding her body with a bright crimson glow. Celestia spent a moment establishing the field, and then pulled backwards, pulling Nightmare's own magic with hers. The crimson of her flaming magic began to mix with swirls of darkness, which themselves glowed a deep electric blue. All this magic flowed back into Celestia, soon enveloping her in a swirling field of her own.
"This is the best way to prevent her from being a threat," advised the voice. Celestia nodded, although she did not want to distract herself too much from the spell. Nightmare Moon was held largely frozen, but her small and frightened eyes locked onto Celestia. Celestia looked into those eyes and for a moment she saw her young sister in trouble.
"Luna?" she thought.
"Focus," reminded the voice. "That is Nightmare Moon. She needs only a moment of weakness."
Celestia mentally agreed and refocused herself, looking away from Nightmare's eyes. She felt the energy beginning to soak into her body, filling her with new feelings. She had felt Luna's magic before, but this was so full of emotion and raw energy. Celestia thought she detected dozens of different signatures in the magic... but all that mattered right now was making sure that Nightmare Moon no longer controlled it.
"She mustn't control ANY magic when we are done," advised the voice.
"She is alicorn," Celestia noted. "She needs SOME magic to survive..."
"I will guide you," comforted the voice. "Keep drawing."
It seemed to drag on for minutes to Celestia, though she realized that the intensity of the spell was distorting her view of time. She observed Nightmare Moon growing smaller as the buffs provided by her enhanced magic drained away. Celestia thought the room was also growing brighter but she continued to focus.
"That should be enough?" she wondered to the voice. "She can't have much more than a standard unicorn now..."
The voice was stern. "Nightmare Moon is still a risk. I will tell you when to stop."
"But even Nightmare Moon..."
"She took your sister! You would risk more?"
Celestia frowned and strengthened the pull, feeling an additional surge of magic as she pulled harder. She barely noticed Nightmare Moon's panting through the thick flame-like aura of her drain spell.
Suddenly she heard an unexpected deep voice from the edge of the room, calling out to her.
"Ah, Princess Celestia. It is so good to see that you have recovered from your injuries."
Celestia blinked in surprise and let the spell go.
"Who the...?" she asked the voice, but it was silent in response.
The spell faded out, the last of the magic absorbed into Celestia's strong body. Nightmare Moon, released from the spell, dropped to the floor with a heavy thud. She was nearly half the size she was when the spell started, her coat a rich blue rather than the deep black, and her mane had regressed to a pale azure blue hair, the plasma gone.
"Luna...?" she asked aloud, and then looked towards the voice. Ulfrid stood near the destroyed door, bowing so that his nose touched the floor. Celestia felt her mind going hazy. "What... what's going on?"
"Ul... Ulfrid..." called Luna weakly. "Help me..."
Ulfrid stood and approached Luna. "All is well, Highness. Your sister has come to visit."
"She.... she came to destroy me..."
"No," comforted Ulfrid. "She is done now. Are you not, Princess?"
Celestia stepped back as a static noise grew steadily in her ears. Her vision seemed to add confusing shadows to everything, and outlines were getting harder to make out. "I don't know... what is going on?"
"It is your sister, Princess Luna," said Ulfrid, sitting patiently.
"No," said Celestia, stepping back again. The static was getting louder and she was finding it difficult to think. "Nightmare Moon took my sister... I sent her away."
"Look for yourself, your Highness," replied Ulfrid.
"I can't... no... I..." Celestia stepped back again, and then turned for the balcony. "I need to leave."
She took a step towards the door, then a second, and a quicker third. By the forth step she broke into a gallop and leapt from the balcony, catching herself with her massive wings and flapping them powerfully as she escaped over the mountains.