Taking advantage of the sudden summoning of the undead, Twilight galloped as fast as she could in the high snow reaching past her ankles. She felt that her best option was to go in the direction of Spike, and with the undead attacking the guards, the trip would be relatively easy.
"She's getting away!" one of the guards said.
He was engulfed in one of the snowy arms of a golem and thrown into another guard trying to dodge several howlers. The unicorns that were there were erecting barriers to push the howlers away, but the spirits were surprisingly tenacious. Their screams were strong enough to make the magic shields rattle and harm the horns of the unicorns projecting them, irritating the group significantly. While their body armor protected them against average magical powers, they realized that whatever the necromancer had done had empowered these entities beyond normal.
"Why is she fleeing?" the first guard wondered aloud. "We need to catch her and knock her out!"
"Is that really going to-Gh!"
The second guard got crushed under an arm of ice that immediately remolded into snow when she was left in the crater. Another soldier engulfed himself in fire magic and, with the help of two earth ponies, flew threw the air in a corkscrew fashion, melted through the necromantic monstrosity, and tended to the wounded.
"She's alright!" he yelled. "The armor took most of the damage."
The first guard slammed his hoof against his armor, scaring off some howlers. "We need to get our antimagic weapons out."
"Why didn't we do that in the first place?!" a soldier shouted. He used his armor to grip onto the head of the snow golem trying to crush him and slammed it head-first into the growing white landscape. "That would have saved us a lot of trouble!"
"Later! I need support against these howlers! Get me a barrier and lace it to two others!" he ordered. "If she's running away then that means she can't use that magic of hers so often regardless of its power!" He furrowed his brow and focused on the shrinking lavender dot on the horizon. "Necromancers always get full of themselves. Push her hard enough and she'll be the same," he grumbled. "A sergeant can still get things done."
Four of the unicorns hopped next to each other, cutting through several howlers with sword and spear and struck their horns together, forming a shimmer barrier around the sergeant and his two accompanying soldiers. They checked their magic limiting cuffs hidden in their armor and rushed forward. As howlers rushed close to them, any attempt to scratch and slice the armor off of their would-be victims was met with the shimmering barrier exploding against their touch and causing them to dissolve on the spot. Unfortunately, with every touch the barriers started to dissipate faster and faster. Their boots had been fitted with small 'plows' on the fronts, so while it didn't give them better traction on the snow, it still allowed for slightly better movement, and with their trained bodies it made the efforts almost negligible.
When they finally reached Twilight, they had to barrel through a newly formed snow golem. One of the sergeant's comrades still had her barrier up and used it to tackle Twilight, causing the magic within it to burst outward against the unsuspecting, panicking mare. She was sent flying, but the impact was lessened by the snow.
"You got her!" the sergeant praised between pants. "Well done!"
"All...in a day's work," the mare stated with a grin.
"Cuff her quickly, in case the spirits are being channeled through her magic," the sergeant ordered. He looked back when he heard the first click around the necromancer's horn and saw the howlers fade out of existence and the golems collapse. He nodded in approval and watched the soldiers start tending to each other and immediately stomped toward the unconscious unicorn. "Thought you could get away with bringing back the dead, huh? Why don't you bring back my parents and use them to torment me?!" he bellowed at Twilight before swiftly kicking her in the stomach.
"I thought you hated them," the mare soldier mused.
She was met with a smirk by the sergeant and the three started dragging Twilight back to the carriages. Of the fifteen that had accompanied him, everypony was injured in some way, although four were too injured to move.
"Alright, everypony," the sergeant started. "We weren't expecting this outcome, but we'll have to make do. I want those too injured to be placed in the first carriage with a medic. Two more will be in the other with...this," he spat as he gestured to Twilight. "The rest of us will walk alongside those pulling the carts. We don't have time to waste and we don't know the extent of our comrades' wounds. They'll be dropped off at our outpost to be stabilized while we continue to the capital. Hurry up and get ready to move out as fast as possible. Am I understood?!" he bellowed.
The capable soldiers slammed their breastplates twice with a hoof. "Yes, sir!" they yelled in unison.
Going all the way back to the Crystal Empire would take days, the sergeant lamented. Their outpost was hidden nearby and their proximity to the event was, at best, a form of 'chance'. He just didn't expect this 'chance' to be so brutal. Fortunately, no pony had died. Yet, and he wasn't about to let that happen. It took about three hours of walking to reach their outpost hidden in a black stone buried under the blizzard of ice and snow, and offloading the wounded was a stressful and tedious process. He was worried that one of them, a young stallion, would lose his leg, but the sergeant didn't have time to think about that now.
He immediately took extra medical supplies and rations with him for the trip back to the capital city and grunted with every freezing step he and the others took. They had to take breaks every few hours to warm themselves up or risk frostbite, but it was worth it to see the face that his rulers would make for delivering him a necromancer.
"Maybe they'll bring out a public execution?" he mused quietly to himself. He shook his head. "No. They're not Sombra, and we're not barbarians, but that still doesn't tell me what they'll do," the sergeant thought to himself.
However strong the barrier was, it had somehow knocked Twilight out for two days. Her awakening was a groggy and painful one, and she clenched her stomach and head in great pain.
"What happened?" she mumbled.
"She's awake!" one of the guards watching her announced.
"Make sure she doesn't try to escape or do anything...uh...stupid," another outside responded. "You know the drill."
Twilight struggled to move but found that her legs were bound together and her magic was being suppressed. She kept trying to escape, thinking that 'just a little more' would snap her bonds. With her magic suppressed, she also wasn't able to activate the medallion, and chanting wouldn't do anything either, unfortunately. As the realization of what had happened to her slowly started to set in, she began to hyperventilate again.
"No! You have to let me go!" she pleaded. The guards looked at her silently. "You have to let me leave! I'm trying to bring back Princess Celestia!"
The pair looked at each other and laughed in unison. The black metal interior of the cabin seemed to rock with the movement.
"Yeah. Sure you are," the left guard mocked.
"Maybe she'll find where Luna fled to as well," the right mused. She lowered herself to Twilight with large, pleading eyes. "Oh, please do. We soooo miss her," she teased.
"It's not a joke!" Twilight cried. "My research! It's important!" Her hyperventilating caused the magic in her body to start going haywire and the ring around her horn to start glowing orange with heat.
"What's going on in there?" the sergeant yelled. A loud 'pop' followed by Twilight collapsing as smoke rose from her body was the response the stallion got. "Oh. Carry on," he said plainly.
After another day, Twilight was physically woken up by one of her captors and looked at him with groggy eyes. "We're a little over an hour to reaching the capital of the Crystal Empire," he said with a smile. "Aren't you excited?"
Twilight's pupils shrunk in horror. Not the capital. Not there of all places! "No! Let me go! Please! I don't want to go there!"
The two guards laughed. "I think she's excited," the second guard said.
"Guess that makes three of us!" the first added.
The immense crystal spire and the light brought by the Crystal Heart at its base brought some relief to the sergeant and his fellows. With its magic the blizzard that once ravaged the land had been focused onto its borders instead, making it all but impenetrable to unprepared outsiders. He couldn't wait to finally get back home, put his hooves in front of a warm fire, and have a nice, warm meal to defrost his bones.
His reverie was interrupted by something catching his attention from the corner of his eyes. It was hard to see with all the white snow reflecting light off of it, but something was coming towards them. Something unaffected by the snow. Something just barely sinking into the cold depths.
"Something is approaching us!" the sergeant announced.
The carriage stopped and the soldiers all jumped out, looking for the threat before following the sergeant's gaze. They didn't want to exhaust or distract each other with questions and so kept quiet. Only the freezing winds flowed between their bodies, nearly freezing them rigid. At first they believed it might have been a polar bear, but the closer the unknown object got, the more apparent the purple colors on its body became.
"It's another undead!" the sergeant announced. "Destroy its c--"
He was unable to finish his sentence as he was kneed in the face by a skeletal dragon, denting his helmet and sending him flying. Stunned by the sudden burst of speed, the others took a second to react when the new undead went directly for the carriage and attempted to pull the doors off without hurting what was inside.
"Take it down!" one of the soldiers shouted.
Spike pushed against the door, giving it some distance over one of the guards trying to stab it with her spear. It promptly brought two fists down onto her back, drilling her into the snow. It sidestepped a sword swipe and twirled around, grabbing the soldier by the head and throwing them into two others that caught the stallion and lessened the damage. Finally aware of what they were up against, the soldiers started fighting together rather than individually.
Two of them tried to stab Spike several times with their spears at random intervals from two different sides, preventing him from moving. This allowed a unicorn to be thrown through the air at its head with her sword outstretched. The undead dodged two more spear strikes and bent its torso to the right, throwing the mare's aim off. Spike brought his body back into its previous position in a flash, bringing its tough head against the soldier's left foreleg and head and sending her slamming into the armored carriage.
Spike stomped on one of the spears, caught the other, and pulled its user towards itself. It whipped the soldier's hooves with its tail then brought a knee to his stomach, paralyzing her. The other one was struck by the dragon's heel when it flipped itself around in the air to create momentum and strengthen its strike.
"We need backup," the sergeant groaned.
He pulled out two red crystals from small pouches in his armor and slammed them together, breaking them apart. The destruction produced a tremendous red flare the size of a two-story house that sparkled wildly several dozens of feet in the air. He smiled and then collapsed into the snow.
Seeing another major threat popping up, Spike changed its attention towards the sergeant lying motionless in the distance. The undead made to catch him but found itself being tripped and slamming face-first into the carriage, denting the surface. This continued for around fifteen minutes of the soldiers taking a different approach to the fight: Keeping their distance.
They realized their hard work had paid off when a pink ball flew past them and struck the undead in its chest, pushing it far back.
"Empress Cadance!" one of the soldiers declared with joy.
Another armored figure, this one fully covered in silvery armor rather than just partially armored with his face exposed, rushed past the two with a halberd on his back. He headbutted the undead that responded by grabbing the stallion's head and attempting to crush it against its knee. It was countered by two hooves striking down and throwing off the dragon's method of attack. Its opponent dropped to the ground and pulled out his halberd, slamming it directly into the undead's skull. He was met with a swift kick and pushed away.
The fighting lasted for several minutes as the undead did not tire and the dragon's opponent dodged and weaved attacks while stabbing and slashing the entity repeatedly with his weapon. Tired and fed-up, the soldier slammed his hoof against his chest and charged into the undead dragon. With all the damage he caused, the magic coursing through his armor disrupted whatever was animating his opponent and caused it to collapse to the ground.
"Tough bugger, isn't it?" the soldier mused. He poked it with the tip of his weapon and hummed. "The magic is still working." He nodded in admiration. "Quite a find, this." The stallion turned towards Cadance looking through the window on one side of the carriage, her face twisted in disgust. "I'll take this with us. Should provide valuable knowledge against the undead in the future."
Cadance wasn't registering anything the soldier was saying. Her contingent of guards was recovering the wounded while she tried to identify who was imprisoned within the carriage. All she could make out was the curled back of the necromancer.
She hummed in disgust. "So this is the one that was causing such an issue that you needed the death threat flare." Cadance focused her eyes, thinking she could see just a strip of color in the mane of the necromancer but brushed it off. "Bring them back to the tower and have them ready for us in the throne room."
"Yes, Your Highness," one of the new soldiers said.