Ahriman's POV

As the Legion marched, I thought back to what I had done to Luna. While she had been close to accepting Chaos, as soon as she realized it before then, she would try to purge it. So I had acted, forcing more of the powers of the warp upon her, which sped up and finished the process. A very tiny part of me felt a pang of guilt, but I purged it. I could see the dark and chaotic forest of the Everfree up ahead. I smiled.

The instrument of their protection shall be their fall. I thought to myself. I sent out my senses to the warp, and sent my plan to the Librarians. They all nodded, before breaking off from the main group. When Luna arrived to lead the assault, many of the soldiers had been shocked at Luna's appearance. I assured them that it was to fight her sister head on, to which they relaxed.

"Lord Ahriman, where are your Librarians going?" Nightmare asked.

"They are going to fulfill a plan I set up." I told her. She snorted before turning back to the forest. Enemy guards had exited after the Librarians had entered the forest, spears raised high. I could still sense the Librarians presence in the forest, so I knew they were safe. Khârn broke formation, his axe held at his side, and walked up to us. Zhufor did the same, his own axe revved up. The guards faltered at this sight, but remained at their positions. As we walked up to them, we stopped.

Me, Khârn, and Zhufor marched up to the terrified ponies.

"Let. Us. Through." Khârn ordered. The guards gulped, but held position. Khârn leered in closer to one of them.

"You will let us through." They held position. He growled before turning back, along with myself and Zhufor. When we got back, we walked into the end of Khârn'sspeech to the forces.

".... and so, we will deliver death and destruction upon their ranks. They chose their path. Now then, CHARGE!" With that, Khârn flipped around, and, gunning Gorechild up, charged right at the Solar ranks. I sighed, then turned around as well, red lightning crackling around my fingertips. Zhufor raised his left arm, and took potshots at the enemy, tearing into their ranks quite literally. Each shot made an entire section of a ponies body vanish. When he got close, he raised his axe.

As soon as they got close enough for close combat, the Legion began fighting with spears, javelins, and anything else they had. Khârn was wading through a sea of blood, his Chainaxe messily tearing heads off left and right. Zhufor could just stomp on them and they would be crushed under the weight of his Terminator armor. He instead tore anypony who got close asunder, be it with his chainaxe, or his bare hands, he ripped them in two, Blood flying out of the bodies of his prey. I, however, was zapping them with lightning, the bolts of energy flying straight at the Solar Guards, due to their metal armor. Granted, some Lunar Soldiers got in the way, but they were collateral. As we tore through them, a gut wrenching cry rang out from behind the Guards lines.

I smiled as Bloodletters rushed out of the forest, trees burning behind them. They savagely cut into the Solar Guard, who were quickly overwhelmed. Before they could begin attacking the Legion, however, silver chains appeared around their necks, and a portal to the warp appeared behind them, and dragged them in. I made sure to temporarily blind everyone, as to keep them from going mad. When the portal vanished, the Librarians stepped out of the forest, each tired. I walked up to them.

"Good job, my Librarians. I knew you had the knowledge to succeed in summoning a group of deamons. But, seeing as you are tired, I will let you rest. Head back, and also, here. A good book to read." I handed them each a copy of the same book, and projected my plan to them. Once they received my orders, they nodded as one before walking back towards the lines.

Once they left, I walked up to Luna, Khârn, and Zhufor.
"It is time to keep moving. We can't let the element of suprise be lost." I told them, and they spoke these words to the Legion they all nodded, and as one, we marched through the forest.

÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷÷

Celestia's POV

As I looked out at the scenery of the Everfree, I sighed, sensing that this day was going to be a bad one. I looked to the Northeast side of the forest to see it burning to the ground. I gasped, before calling for the guards to investigate. When they came back, they reported that an entire Company of Solar Guards had been wiped out. I then proceeded to mobilize the remainder of the Solar Guard to position themselves near the palace. I walked to the throne room, but stopped once I saw that all the guards there were dead. I immediately took up a defencive stance.

Laughter filled the air, cold, cunning, and evil. Before my eyes, a Midnight black Alicorn stepped out from behind the balcony. She looked like Luna, but taller, with wavy purple hair, glowing green serpent eyes, and sharp teeth.

"Sister. It has been a while." The Alicorn spoke, causing me to gasp. It was Luna!

"Sister, I implore you. Please stop this madness! We were meant to rule together, not fight over it." I pleaded, but she only laughed.

"Did you really think that with just words, I would go back to being you lapdog? You really are a fool." She then charged up her horn. Right before she launched her attack, I got a sense of her magic. It was vile, like polluted water, and I felt the Chaos it contained. I prepared to dodge it, but instead, she fired it up into the sky. After a moment of silence, a war cry sounded out.

"BLOOD FOR THE BLOOD GOD SKULLS FOR THE SKULL THRONE!" A voice shouted, and an entire army burst from the trees, causing the Solar Guard to jume before readying their spears. I looked back to Luna, who sat there with a smug smile.

"Luna... how far you have fallen." I told her, and charged my own horn. She snorted, before doing the same.

(Note: I am not good at writing a battle like this. You have been warned. Also, it's much like the battle we all know of.)
Third Person POV
As the first shots began to fly out, Celestia and Luna succeeded in destroying the ceiling on the castle. They rose in the air, watching eachother. Then, Celestia made a move. She shot a concentrated burst of magic, which Luna dodged around easily. She shot multiple beams, but to no avail. Luna shot back, a massive beam of chaos-imbued magic, which tore straight through a wall and out the other side, causing the massive structure to collapse. Celestia charged at Luna, horn raised at her heart. Luna leapt in the air, before punching down with her hooves, right into Celestia's back. Celestia cried out in pain, before falling into the Room of the Elements. She could tell that she couldn't beat Luna, especially due to the Chaos that had claimed her.

She sighed in defeat, before summoning the six elements. Luna looked down on them warily, the son da of combat just now reaching their ears. Below them, ponies and batponies died at eachother's throats, both sides fighting for one reason or the other. Khârn had killed at least two whole companies worth of loyalists, with Zhufor doing the same, though at a slower pace. Ahriman had already entered the palace, tearing into any guard that remained inside.

Returning to Luna and Celestia, Luna laughed.

"Listen, sister. Listen to the sound of your soldiers being destroyed. Does it not please you? Does it not please you that your precious guards would die fighting for you? Because each of their souls won't go to heaven or hell. They will go to the warp, as playthings for Tzeentch." She gloated, which received a pained look from Ceoestia. She looked at the elements.

Please, save my guards. Save us from Chaos. I beg of you. Restore harmony to this world. I pleaded, to which the Elements started to glow. While Luna laughed, a beam of Rainbow energy flew out of the elements, which hit four things: Luna, Ahriman, Khârn, and Zhufor. They all screamed as they felt the power of Harmony flood into them. They all vanished without a trace, but the moon, which had risen high in the sky, had the image of an Alicorn, with its eye being a Eight pointed Star.

Celestia looked at it, the realization of what had happened slowly dawning on her. She then cried out, tears streaming down her face. The Solar Guards, who now had the advantage, quickly finished off the last of the Lunar Soldiers, and those that didn't flee were captured, and then executed. The 45th Company escaped, with little more than twenty survivors, out of a group of fifty. No one knows what happened to the remnants of the once proud Lunar Guard, some believing that they all died off, some believing that they were biding they're time.

After many years, much of the history of this Civil War was lost, and no one knew how the Lunar Guard suddenely got so powerful.
And now, after a thousand years, the Warriors of Chaos would return, spiteful and full of Malice.

"And so, the elder sister used the most powerful magic of all, The Elements of Harmony, to defeat Nightmare Moon, and imprison her in the moon." Twilight finished. "Mare in the Moon... I know I've heard that legend somewhere." She pondered as she walked home.

Author's Notes:

And tadaa! The Civil War Arc is finished! I've got a few plans for the next part! I hope you enjoy!