Before anyone could react to the intimidating sight, Celestia raised her head and gave a high pitched, almost primal shriek, eyes shooting wide open as her pupils rapidly contracted. Her entire body went rigid as two tendrils of fiery magic shot from her horn and wrapped around her torso, growing thicker as five more joined them until her entire body was hidden beneath the flames.
"Princess Celestia!!" Twilight cried before she could stop herself, horn flaring to life as she tried to rush forward. Spike caught her before she could move out of reach and pulled her back, using all his strength to keep her from struggling out of his grip.
"Twilight, don't! You don't know what's happening!" He told her as he managed to pull her back against his chest. She relented in her efforts but looked up at him sternly.
"Yes I do! And so do you!"
If Caligo could hear the commotion, it didn't give any indication. Its gaze remained locked on the fireball that Celestia was inside, watching as the magic condensed into a sphere surrounding her, quickly glowing brighter and burning hotter. Within seconds it became too intense to look at, forcing Twilight and Spike to shield their eyes, the dragon shifting his position round to in front of Twilight to keep her sheltered from the heat. As the combination reached unbearable levels the scream stopped and the magic collapsed into a blinding shockwave that blasted out in every direction, searing everything it touched. Spike grunted in pain as he bore the hit across his back and even Caligo was staggered from the intensity of the wave. As the light reached normal levels again all three looked to the epicentre of the blast and froze in shock.
Celestia still stood there, though her figure and cutie mark were the only things that remained the same. All her royal attire had gone, melted into a eerie puddle at her hooves from the intensity of the heat. Her coat had shifted from pure white to ivory. Her mane and tail now flickered rather than flowed and the gentle colours had been replaced with those of fire, burning orange at its core and shifting to red as it rose upward before the contact with the air turned the solid colour to a clashing mix of blue, green and white. Her pupils had shifted from a natural round shape to that of a jagged flame and the whites of her eyes were a murky tan. Most concerning were the glowing orange cracks in her skin that ran from the base of her horn, down into her eyes and on to the sides of her neck before halting at the base of her wings.
Her lekli, in all its terrifying glory.
"Ooooohh, finally," She said in that same smooth, dangerous tone, rolling her neck as she brought her head back down and shook a hoof, as though getting a feel for the form she had now. "You're lucky, Caligo, getting to share your body with Kosung sometimes. Do you have any idea how it feels to sit in silence for tens of thousands of years, watching your waste spread over the world?"
"You...Who are you?" Caligo asked in fear, taking another step back. It seemed to know the answer but didn't want to hear it.
Celestia simply raised her head and laughed. A harsh, mocking laugh that echoed through the halls of the tomb even as she finished and focused in on the spectre with a ferocious intensity.
"I, am Ortasin. The better, prettier and more powerful version of that traitor to our race, Vaeac!"
"No..." Twilight whimpered quietly as she watched the developing situation from the entry tunnel. Seeing her beloved mentor twisted like this, into one of the nightmares she had effectively been fighting her entire life, was tearing a hole through her heart, a feeling that was only compounded as Spike let her go and put a hand out to lean against the wall. It was enough for her to see that his back was smouldering from the blast, his resilient scales scorched black. Such magic must have caused him indescribable pain, yet he had remained standing, likely through sheer willpower more than anything else.
"Twilight..." He said quietly, sitting down and placing a hand on her shoulder. "Sorry to heap more on you but, I'm a little overcooked here. Celestia needs help out there. If anypony can save her now, it's you."
Twilight hesitated for a moment before realisation flashed through her mind. There wasn't time to panic or worry in the middle of a crisis, she had to focus and use everything she had learned both today and when facing Nightmare Moon. It was another situation where the fate of Equestria was on the line, as any kind of failure on her part would leave nopony strong enough to stand up to Ortasin. She couldn't fail Celestia here. She wouldn't. Her expression hardened to one of determination and she nodded.
"I'll find a way. Spike, get to safety."
"I'm safe enough here. No way I'm letting you deal with this all alone," He told her, leaning forward to keep his back off the wall. "Besides, I might need to pull your tail out of the fire again."
Her face softened slightly at his loyalty and she gave him a quick hug of thanks before turning and facing the chamber again. It seemed Ortasin had kept her priorities elsewhere during their discussion and was now advancing on Caligo, wings flaring out as the spectre turned to flee.
"Ah ah ah," Ortasin tutted as her horn lit up, her magic a fiery flickering yellow that made the cracks in her skin glow brighter. The same light quickly enveloped Caligo and pinned him in place before forcing the larger alicorn to face her again. "You didn't think I was just going to let you leave without some response, right?"
"Well, I...Errr..." Caligo stammered, struggling to gain any purchase against the grip it was held in. For the first time, the calm demeanour in its voice was shattered, replaced by genuine fear. "H-hail Empress Ortasin?"
"Oooh, Empress. That's got a nice ring to it. Flattery like that might even keep you alive. " She flashed a momentary smile before leaning in close with a dark look, magic sparking from her horn as the energy built up. "Implying that I'd let you out to share this world with me though, I can't forgive THAT!"
As she roared the last word her eyes glowed with ferocious intensity and her mane burned white hot, the incredible heat radiating from her enough to ignite the dust hovering in the air. In the blink an eye the chamber was engulfed in a firestorm and Twilight was forced to throw up a barrier to protect herself and Spike from the blaze. Though the flames kept them from seeing anything, they could hear the unmistakable whine of magical power being constantly ramped up stronger and stronger, followed by hysterical screaming. Neither had any idea what was going on, nor did they want to know. When the fires cleared half of the vast room had been completely scorched and only Ortasin remained, her mane colours returning to the mixed fires of before.
"Ohhh, you ran back into your walls?" She said as her magic ceased, her glowing parts returning to what passed for normal on her, her voice taking the tone of a parent chiding their foal for misbehaving at first before calling out down the halls. "Let this wretch serve as an example to the rest of you watching! You can have your hole in the ground, and your lives, so long as you keep yourselves away from my empire!"
Twilight tensed herself slightly. One way or another, she had to move now if she wanted to keep things contained here. With a last look back to ensure Spike was still okay she dropped the barrier and stepped forward, unfurling her wings in a gesture of blocking the exit. Ortasin's ear flicked at the sound of magic deactivating and she turned to face the smaller alicorn with a look of curious bemusement.
"Oh, Vaeac's little pet project," She mused as she turned fully, her voice back to its venomous charm. "Twilight Sparkle, yes?"
"You know who I am?" Twilight asked, her own ear flicking in irritation at being referred to that way.
"You can understand me?" Ortasin countered in momentary surprise before shaking it off. "Of course, Vaeac would make sure a prize like you would be prepared."
"What do you mean?"
"Every moment she's been wasting our time on trying to guide a land full of defects to fruitless endeavours, I've been forced to sit and watch, seeing everything she tries. Most of her actions would have seen the true empire calling for her head, but her work toward 'ascended' alicorns...That actually impressed me. The first one, Cadance was it? She was a decent test for the magic but applying it to a powerful pony like you...With a power jump you could have actually passed for an alicorn approaching the middle of the castes."
"You really think that I would just agree to work with a race only interested in their own selfish interests, just like that?" Twilight responded firmly, standing her ground even more than before.
"Defiance born of ignorance," Ortasin replied matter-of-factly, shaking her head slightly. "It's funny, I wouldn't normally have such tolerance of insubordination. But seeing what both Vaeac and I made you into, part of her must have rubbed off on me a little because whether through lack of options or genuine interest, I do see you like a daughter figure."
Twilight barely kept herself from recoiling, internally offended at the audacity of such a statement.
"That's why I'm giving you this chance," Ortasin continued, taking a step forward, her tone actually softening. "Your magic still isn't close to mine, but I can teach you, finished what she started. Between us, we could help everypony out there ascend to their rightful position, undo the damage done when the empire was ruled by the wrong hooves. Come now, little one, help me save our race."
Twilight simply remained rooted in place this time, staring down the threat in front of her. There was no chance of her willingly helping in any way after everything she had been told today, but even less chance of her being able to defeat an alicorn as powerful as this in a straight fight. Not that she was she sure she even could attack her opponent, she was still Princess Celestia beneath all that. That thought sent a momentary twinge of fear through her before being suddenly replaced by clarity. An idea of how she could break through to the princess. All it required was to get within a foot of the most powerful and dangerous being on the planet without getting blasted. No pressure then.
"I..." She replied slowly, looking back at Spike. He was in bad shape, leaned up against the wall and panting hard, clearly struggling after the hit he took. Her eyes met his and she gave a silent wink, hoping he was getting the message she was trying to give.
Please, trust me on this.
"So, you just want a peaceful rule that will allow the alicorns to survive?" She asked, hoping she looked curiously optimistic as she looked forward again.
"Yes!" Ortasin replied in relief. "Even I can agree with my worse half that there's not much point leading an empire of four."
"And you promise everypony's safety if you lead Equestria?" Twilight continued as she relaxed herself, taking a step forward. The fact there was no sound from behind her was a silent relief.
"Of course," Ortasin replied happily. "Even those that don't want to be ascended right away will be begging for it when they see how good life is as a real alicorn."
"Then, maybe we can work out a compromise of sorts." Another few steps. Just a few more and she'd close enough to touch at a stretch.
"I'm glad to hear it. Though I should warn you in advance that there will have to be..." The lekli's gaze turned to Spike with a sudden intensity. "Exceptions."
Twilight's instinct kicked in almost before Ortasin's horn started glowing. She pushed herself between the two and threw up her strongest shield just in time to intercept the attack, flames licking away at her magic as the main blast crashed against it. Though the shield held out, the force knocked Twilight out of the air and she rolled as she hit the ground hard, knocking the air from her lungs and sending her skidding to a halt back at the exit.
"Twilight!"
"I'm okay." She gasped as she looked up, convinced she wasn't badly hurt from the attack.
She had distinctly heard three voices cry her name, all of them familiar. Spike had been one of them, the other two had come a little after but at the same time as each other. More importantly, they had been both Ortasin AND Celestia. As she looked back toward the lekli she noticed that she was being watched with a look of concern, through normal, magenta coloured eyes. It hadn't been the original plan but it was doing some good. Now she just had to help Celestia keep fighting back and if that meant remaining in harms way, so be it. As Ortasin blinked her eyes shifted back to gold, though the pupils remained normal.
"Knew it," She remarked coldly, her horn, eyes and cracks all glowing as she began to advance. "Some ponies just can't be trusted anymore. I suppose killing you both will have to be my warm-up before the rest of the world feels the flames of destiny."
"You'll have to take me first." Twilight growled as she got up fully, rushing toward Ortasin and firing a beam from her horn. Although the larger alicorn dodged the attack with ease, she had taken off at the same time and dashed in close, swinging a hoof that caught a glancing blow against Ortasin's shoulder before flying off into the far right hallway.
"You DARE lay a hoof on a goddess!?" Ortasin roared, all pretence of control lost as she fired a wide shot at the exit before flying after Twilight.
As far as plan Bs went, Twilight had to admit to herself that deliberately angering an evil version of the princess of the sun was among the worst she had ever come up with. It was a necessity this time though. Celestia was the only pony powerful enough to stand up to Ortasin and if driving her to attack was the best way to help her mentor fight back then she would do it without hesitation. The halls of the tomb passed by her in a blur as she constantly twisted and span in mid-air to avoid any kind of assault, barely able to focus enough to see upcoming corners, let alone anything else around her. She could still hear Ortasin was right on her tail though, chasing her down and occasionally firing bursts of magic that connected with nothing but the walls. At this point it was hard to tell if the rarity of the attacks were down to not wanting to risk the tomb or Celestia's influence.
"If you were powerful enough to lead, wouldn't this be over by now?" Twilight called back as she threw herself into a tight right turn, her wingtip brushing the wall as she moved onto a straightaway. Taunting wasn't really her thing as the Princess of Friendship but she needed to keep her opponent fired up enough to attack, which in turn would drive Celestia to resist. The only response this time was a furious snarl.
A sudden flash from behind her was the only warning she got before Ortasin teleported twenty feet in front of her and gripped Twilight in her magic, extra pressure being applied to her neck and chest. Twilight gave a strangled gasp and tried to stop herself only for her world to become nothing but white pain as her aggressor used the momentum to swing her round and choke slam her into the wall. The pain spiked as her body hit the wall at an angle a moment later, crushing her left wing between stone and body as the magic grip on it intensified.
"You, stupid, pest," Ortasin panted as she leaned in closer to the writhing alicorn. Her words sounded strained as though she were fighting to get them out. "Not smart. Any...Last, words?"
Even through all the pain, Twilight saw it. Her last chance to save Celestia and all of Equestria. She forced herself to relax her body and get the words out.
"L...Look me in the eye...As you...Do it."
She tensed as Ortasin smirked and lowered herself in closer, locking her eyes on Twilight's as her horn glowed with fiery energy, the tip aimed right between her prey's eyes. The heat from her mane radiated like a furnace that seemed to cook the air around them and left Twilight struggling to breathe even harder.
"You've, earned a quick...First death for your, blind, foolishness. I'll just find, a way to bring you....You back and..."
Seconds passed. The attack never came. The temperature in the corridor dropped slightly.
Ortasin had tensed up, eyes shut tight, jaw clenched. Twilight gritted her teeth as the magical grip on her throat tightened enough to throttle her completely for a moment before loosening again.
"No..."
That was Princess Celestia's voice.
"Stay out of this..."
Ortasin's fired back a moment later but it was shaky. Her focus had shifted from killing Twilight to containing her other half. Even as she kept speaking her voice kept changing between the two, Celestia's growing stronger with each word.
"I, won't let you harm her more."
"You don't get a say in what I do with a reject!"
"That 'reject' is like a true daughter to me! I'll tear you apart myself before you lay another hoof on her!!"
"Really? You can't destroy me. I'm everything you should be!"
"I will see you cast back to the darkness you belonged to, and you will never exist again!"
"GET OUT OF MY HEAD!!!"
Ortasin cried out in frustration and pushed her head forward as she fought her internal struggle, almost impaling Twilight on her horn. It put her close enough to attempt plan A again while this opening was there. Twilight twisted her head round and forward, pushing through her inability to breathe as the magic pressed her throat harder, managing to get the tip of her horn to Ortasin's forehead. Her magic sparked to life and fired a spell directly into her mind. It was an old tactic, but it had worked wonders when she and her friends first faced Discord.
Projected memories of all the times Celestia had spent with Twilight, twenty years of the closest kind of bond they had shared with each other, their familes and friends. Everything that was at stake if she lost this struggle. Hopefully it would help motivate her enough to win the hardest fight of her life.
Ortasin screamed as the cracks in her neck shot blinking streaks of light from within that engulfed her entire body. The magic holding Twilight faded completely and she dropped to the floor, clutching her throat as she fought through the pain wracking her body. Within seconds the light faded and a figure collapsed to the ground next to her. After a moment they stirred and reached out, gently touching her shoulder with a hoof.
"Twilight...?"
Twilight could practically feel all her pain and fear melt away in a heartbeat as she raised her head.
"Princess Celestia..."
It was her. She looked awful, as though she hadn't slept or eaten properly in a month, her royal regalia still missing, but it was unmistakably, completely, Princess Celestia again.
Twilight..." Celestia said softly as they both pushed themselves into a sitting position, tears welling up in her eyes. "I...I'm, so sorry. I should never have made you-"
Twilight silenced her with a hug.
"You weren't the one who hurt me," She told her mentor quietly, failing to keep tears of her own contained. "All that matters right now, is that we're still here. I forgive you, for everything."
Celestia gave a small happy sob and embraced Twilight fully, taking care not to touch her injured wing. For a minute neither of them moved, simply letting everything out. The stress, the pain, the sheer relief at seeing each other alive despite all they had suffered through today. There would be time to deal with everything that had happened later. Right now they were in silent agreement on what needed to happen next, helping each other up to their hooves and bracing themselves on each other as they slowly made their way back to the main chamber.
"Twilight..." Celestia said as they reached the ash scarred remains of the entrance again, looking down at her former student and managing a small smile. "Thank you."
"You were the one who had the resolve to defeat Ortasin. I only gave you a boost." Twilight replied, wincing as she adjusted her wings.
"It was still a battle I could not have won without your help. I just hope I can find a way to repay you someday."
"Does that mean we're done here?" Spike's voice drew their attention toward the exit where he was still waiting, sounding a little better after the short respite provided by being out of action. Twilight smiled softly at seeing him improving and nodded.
"Yeah, it's over. Let's get out of here before we wake up something worse."