The cold wind rushed through Luna's mane, she could feel every muscle in her body tense and relax with each powerful stroke of her wings, easily overcoming the winds at this high altitude. She felt exhilarated, it had been some time since she had a chance to fly any great distance alone and at speed. Relishing in her temporary freedom, Luna flew onward.

Celestia's sun was just beginning to peak along the horizon as she cleared the Crystal Mountains. The strong gusts of wind changed to a blizzard, heralding Luna's arrival into the Frozen North. It did not slow her, with a quick spell that heated her fur, the ice and snow could not find purchase on her body. She could however do nothing for the lack of visibility that the snow brought. Only the faint light from her sister's sun kept her sure of her direction.

Being sure to check her direction every minute, Luna allowed her mind to wander.

"We remember when this land was lush and green." she thought sadly, a brief image of Canterlot, frozen and desolate passed through Luna's mind before she pushed it aside. "No." she thought resolutely. "It will not come to pass."

Once more checking her direction, she angled herself ever slightly and pushed forward through the blizzard. The wind and snow ceased suddenly when Luna broke free of the storm, allowing her to see for miles around her.

"By our father." she breathed.

Below her and for several miles around the ground was dead and black. It looked as if a terrible fire had razed the earth but Luna could sense the sickness radiating upward, a sickness only dark magic could inflict. Her eyes traveled upwards to the heart of the sickness. A massive black fortress in the skies above the ruins of the Crystal City was the cause of this corruption, one could feel the evil surrounding the structure.

"What new devilry is this?" Luna muttered to herself, angling her flight as she descended. Alighting upon the blackened earth, the corruption was so strong that she could smell it.

Eager to be away from this place, Luna cast a spell to allow her voice to carry upwards.

"Let the lord of the black fortress come forth!" Luna shouted in her magically augmented voice. "We are Luna, Princess of Eqestria and we have come to treat with thee!"

As her shout faded, there was no immediate answer. Luna stood in silence, prepared for whatever came next. The still air began to stir, rising to a howl as a whirlwind whipped across the landscape, bringing with it an otherworldly laughter. The laughter increased in volume as did the howl of the wind and as Luna watched the whirlwind turned black as the pits of Tartarus before congealing into a large stallion clad in black armour.

The wind died abruptly. Sombra smiled a wicked smile as he bowed mockingly to Luna. “Princess Luna. Welcome to the Crystal Empire."
He stood up, smile still in place. "You do me a great honour. Tell me, to what do I owe this pleasure?"

"Save your sly words." Luna said sternly. "We have come to parley for the lives of those you hold prisoner."

Sombra's eyes flashed red. "Is that so?" he said in mocked surprise.

Luna ignored his mocking tone. "Mine sister and I will acknowledge your right to rule as well as your sovereignty over the north. We also extend a hoof of friendship between our two nations. In return we ask only for those held prisoner by you."

Sombra chuckled slightly before responding. "A most generous offer, your majesty but as you can see." He raised a hoof skyward. "My right to rule now extends far beyond the north."

"Enough!" Luna said, angrily. "We tire of your words! Return to us the captives!"

Sombra's smile grew darker. "As you wish." His horn crackled with dark magic, conjuring a large burlap sack. Dark liquid dripped from the bottom of the sack as Sombra used his magic to throw it at Luna's hooves, scattering its contents before her.

A cold pit formed in her stomach at what she saw. The severed heads of Cadance and Shining Armor stared at her as well as the head of the young private who had accompanied Steadfast. The three held her gaze with ones devoid of all life. The cold pit turned to one of quiet rage as Luna looked back to Sombra, hate evident in her eyes. "Murderer." she said, with barely contained rage.

Another laugh echoed across the wastes but did not come from Sombra. Whirling shadows swirled beside him, taking the form of a small purple unicorn mare dressed in black robes.

A fanged smile that rivaled Sombra’s spread across her face. "It’s good to see you again Luna." Twilight said

Luna could only gape in disbelief, praying that she was mistaken. "Twilight?"

"Indeed." she said with no small amount of mirth. "What do you think of my new look, Princess." Here she turned sideways, drawing attention to the black robes that clung tightly to her body. The robes were cut just so as not to hide her cutie mark or hamper her movements, rising up into a low collar that hung just below her throat, and upon her head sat an iron crown similar to Sombra's.

Luna did not reply. Sombra eyed Twilight, a hunger present within them. "You do look lovely, my dear."

Twilight glanced sideways at him, a dark glint in her eyes. "Thank you. I figured it was time I dressed appropriately."

She turned back to face Luna who was still evidently struggling with this most recent turn of events. "It’s funny." Twilight said. "Everypony automatically assumes that Sombra is the one who killed them." She motioned towards the severed heads at Luna's hooves. "When in fact, I was the one who took the lives of Cadance and Shining Armor."

This admittance snapped Luna out of her daze. Turning her burning gaze unto Sombra. "Monster! What foul magic hast thou employed to ensnare the mind of Twilight!?"

Twilight laughed, forcing Luna to return her gaze towards her. "You are very mistaken, princess. You see, I joined him willingly." She took a step forward. "I killed Cadance, willingly." Another step forward, eyes glowing red. "I killed my own brother, willingly." Yet another step forward, magic pulsing through her horn. "And now I will kill you with great eagerness and pleasure."

No sooner had the words left her mouth did Twilight fire a massive beam of dark energy at Luna. The beam cut a swath of destruction as it tore through the ground where Luna had been standing seconds before.

Luna hovered in the air several yards above the field, quickly charging her own spell. She fired her own beam of energy at Twilight who had yet to recover from her own. Just before the beam made contact a wall of black shadow erupted before her, absorbing the brunt of Luna's attack before sending the remnants back at its source.

The backlash struck Luna with enough force to send her toppling through the air but not enough to wound her. A quick teleportation spell brought her back to the ground already preparing for her next attack.

However before she could act, Luna heard a faint sound off to her left. She ducked just as a crimson blade passed through the air where her neck had been. Again, the noise sounded, this time behind her. Quick as lighting, Luna spun in place and brought her fore hooves together, catching the crimson blade inches from her face and allowing her a look at her attacker.

A haunting suspicion that had burrowed into Luna's mind with the revelation of Twilights betrayal was confirmed for smirking at her from inside a black hood was Rainbow Dash.

"Not you as well." Luna said.

Rainbows smirk only grew darker. Arching her back, Rainbow Dash pulled her sword from Luna's grasp and slammed her back hooves into her jaw.

Luna staggered back, loosing a spell at Rainbow Dash as she did so, but Rainbow Dash had already disappeared. She reappeared several yards away from Luna, allowing the dazed princess to regain her senses.

"Nice outfit, Rainbow." Twilight said, taking the break in the fighting to compliment her friend’s new attire.

"Thanks. I was going for the dark ranger look." She motioned down, indicating the dark leather chest piece as well as the black cloak attached to the hood.

Twilight moved to respond but was interrupted by Luna.

"Traitors!" Luna shouted, spitting out a large glob of blood. "You banter as if it were a holiday. Can you not see that his evil has corrupted you?"

"On the contrary." Twilight said. "His evil as you call it has freed us. No more our we bound to the fate you and Celestia created."

"Do you not hear yourself?!" Luna cried out, desperation entering her voice. "He has twisted your minds! Turned you against the very ponies who needed you!"

"No." Twilight sneered. "He only lifted the veil of lies that you and Celestia sought to keep over me."

Luna looked towards Rainbow Dash who stood some distance from the others, hoping she’d see reason. "Surely you are not so easily deceived? Remember where your loyalties lie!"

Rainbow Dash stared at Luna with cold indifference as she shrugged. "I don’t know if he's lying and honestly I don’t care." She glanced towards Twilight. "I'm loyal to Twilight and so long as she follows him, so will I."

Desperation turned to anger. "Then you are truly lost." Shouted Luna. "Its fortunate that Applejack did not live to see her friends succumb to the very evil that ultimately claimed her life!"

A visible shock ran through both Twilight and Rainbow Dash. "What did you say?!" snarled Twilight.

A small shred of hope emerged, one Luna took hold with all her might. "Aye." she said. "Applejack died of a crystalized cancer not one day passed."

"That can’t be!" Rainbow Dash said. "She only had a mild cough when I left!"

Luna shook her head sadly. "It quickly spread throughout her lungs, we could do nothing but watch as it slowly consumed her." Luna pointed a hoof at Sombra. "Foul black magic that he brought to this world killed Applejack. Do you not see?! He will not hesitate to do the same to you when your usefulness to him has expired."

Having finished, Luna watched the two elements carefully. Rainbow Dash seemed racked with indecision but Twilight remained stoic. Only Sombra appeared calm.

Finally Twilight spoke but when she did what little hope Luna had of turning them from their path was lost.

"Sombra." Twilight said calmly. "Weaken her."

An evil grin spread a crossed his face, magic charging within his horn. With a roar he unleashed the pent up magic, conjuring a massive dark green hammer that he brought down unto Luna.

Panic swept through Luna as she channeled power into a shield, just as the hammer reached her. A mighty thunder crack sounded across the land from the hammers blow, driving Luna down into the ground. Her shield held, but only just.

Sombra raised the magical hammer skywards before bringing it down once more. Again, a thunderclap sounded. Luna poured more energy into the shield but could feel it beginning to fail.

One final hammer blow buckled Luna's knees and shattered the shield, leaving her drained and barely standing.

"Rainbow." Twilight said. "Take off her horn."

Ragged breaths escaped Luna as she watched Rainbow Dash hesitate for a moment before disappearing in a mass of shadows. Luna heard her reappear, knew the direction from which the strike would come. She moved to parry but was to slow.

She screamed in pain as Rainbow Dashes crimson blade sheared her horn from her head. A magical shockwave erupted from her destroyed horn, blasting her backwards onto the ground where she lay, panting.

Stars danced a crossed her vision. She struggled for breath, each time she exhaled the darkness at the edges of her vision encroached further. A shadow passed over her and for a moment Luna thought she had lost consciousness. Instead it was Twilight who placed a hoof directly on her chest and pressed firmly down, further limiting Luna's ability to breath and forcing her to look into her eyes.

Luna longed to see pain or regret in those eyes, instead she only saw the cold expansions of the void. "You were meant to defeat Sombra, not join him." she managed to choke out.

Before Twilight could respond another shadow passed over Luna. A fanged smile and glowing red eyes gazed downward at her broken form. "It seems you have been bested, Princess." He finished with a sneer.

His horn glowed softly, levitating Luna's severed horn between him and Twilight, just above Luna's heart. The soft glow of his horn changed to crackling lightning as he channeled dark magic into the broken horn, which became cracked and twisted with corruption.

Using what was left of her strength, Luna glared at Sombra in defiance.

"Die, now." Hissed Sombra, raising the twisted abomination before plunging it downward.

“No.” Twilight said suddenly, causing Sombra to halt his downward strike. His gaze turned towards her. “No?”

“No.” Twilight said again with force. “I've thought of a better use for her.”

Sombra let out a threatening hiss, his eyes glowing red. “Why wait? The Alicorn is broken. It must die!”

“And she will.” Twilight responded, fixing Sombra with her own glowing red eyes. “Just not yet.”

They held each other’s glare for a moment, neither giving in, until Sombra turned away with a snarl. “Until next time, your highness.” Using the twisted horn, he slashed a crossed Luna’s right eye, leaving a deep bloody gash, before tossing it onto her chest.

Luna writhed in pain, held in place by Twilight. She barely acknowledged the feeling of Twilight grasping her head between her hooves and drawing her close.

“Send my regards to Celestia.” Twilight said, horn pulsing with dark magic.

Luna’s next feeling was that of falling.