Princess Celestia sat on her throne, signing some documents for a well-styled mare as two members of her Royal Guard stood stoic on either side. Suddenly, another member of the Royal Guard burst through the doors of the throne room. "News from northern Equestria!" he exclaimed as he galloped toward her. "Uh, Your Highness." He stopped and bowed at her hooves.
"Yes?" the white alicorn replied.
The earth pony guard removed his helmet. "I am simply to tell you that it has returned," he declared with a nervous look on his face.
Princess Celestia gasped. She turned to the guard on her right. "Find Princess Cadance and Shining Armor"
"Yes, Your Highness." The guard bowed and all three guards galloped off.
Princess Celestia picked up a quill and a sheet of paper with her magic and began writing to her star pupil. My dearest Twilight; you must come to Canterlot at once. She finished her letter and sent it off to Spike. Then, she flew off to find her sister.
She found Princess Luna in her room. "Dearest sister, I have just received word that the Crystal Empire has returned once more."
The blue alicorn was just as shocked as her sister was. She stood. "But how can that be? Sombra -"
"I don't know," she replied, "but I've already sent word to Princess Cadance and Shining Armor, and I've sent a letter to Twilight Sparkle, requesting her presence."
"It is time, then."
"Yes."
The next morning, after they raised the sun and lowered the moon, the walked back to the throne room, awaiting Twilight's arrival. They stopped in front of a stained-glass window, the one depicting Princess Cadance and Shining Armor's wedding, and how their love had saved Canterlot from being overtaken by Queen Chrysalis and the Changelings.
Princess Luna asked her sister, "Are you sure you don't want me to go as well?"
"Yes. Princess Cadance and Shining Armor are already there. The others will be joining them soon." Princess Celestia addressed her sister.
"The Empire's magic is powerful," Princess Luna replied, and she looked back at the window. "It can NOT fall again, my sister."
The white alicorn nodded her agreement. "She will succeed at her task. And when she does, we'll know that she is that much closer to being ready."
"Ahem." A purple unicorn announced her presence, and the two sisters turned toward her. Twilight Sparkle stood in the doors of the throne room and gave them a nervous smile.
Celestia smiled back at her, then turned to her concerned sister. "Trust me, little sister," she said confidently while Princess Luna walked away.
The blue alicorn looked at Twilight as she passed her on her way out of the hall. The blank look she wore did nothing to ease the purple unicorn's nerves.
"I brought my own quills," she said as she lifted her saddlebags, filled with supplies, off her back. "And plenty of paper to show my work." One of the scrolls opened up and rolled all the way down to Celestia's hooves. Twilight anxiously nudged it with her head to try and roll it back up. "Sorry, sorry!"
Celestia instead rolled up the scroll with her magic and declared, "This is a different kind of test." She replaced all of Twilight's books, scrolls, and quills into her saddlebags. Then, she bowed her head, giving her star pupil a grave look. She looked back up. "The Crystal Empire has returned."
Twilight sat upon the floor. "The Crystal Empire?" She pulled the books she had brought out of her saddlebags. "I'm sorry, I - I thought I'd studied." She tossed each book aside, and Celestia caught them with her magic. Twilight's voice became shakier and higher pitched. "Oh, I don't think there's anything in any of my books abou-"
"There wouldn't be," The white alicorn interjected. Twilight stared at her teacher, her mouth hanging open. "Few remember it ever existed at all." She walked over to the throne, where a crystal sat to one side, under a glass dome. She lifted the glass and retrieved the crystal. She placed the crystal on the ground in front of Twilight. "Even my knowledge of the Empire is limited." Celestia shot the crystal with magic, and the crystal revealed an overhead view of what the Empire looked like. "But what I do know, is that it contains a powerful magic."
She continued explaining the story of the Empire, showing it through the crystal's illusion. "One thousand yeas ago, King Sombra, a unicorn whose heart was black as night, took over the Crystal Empire." The illusion turned desolate, and black crystals grew on the castle in the center. Sombra's head appeared atop the tallest tower. His head gave a sneer, and now, the illusion shifted to show the crystal ponies enslaved by him.
"He was ultimately overthrown, turned to shadow, and banished to the ice of the north," she explained, as the illusion showed the silhouettes of her and her sister battling King Sombra. Once again, the crystal showed the Empire. "But not before he was able to put a curse upon the Empire, a curse that caused it to vanish into thin air." At this, the illusion ended, leaving Twilight staring at the crystal before her.
Celestia lifted the crystal, smiling. "If the Empire is filled with hope and love, those things are reflected over all of Equestria." Another shot from Celestia's horn sent a rainbow of colors to radiate from the crystal. She shut her eyes and her face contorted into a mix of fear, anger, and sadness. She was remembering when she had battled Princess Luna as Nightmare Moon, and foolishly banished her to the moon. "If hatred and fear take hold," she opened her eyes. They had turned completely green, and they emitted a purple haze, just as King Sombra's had.
Black sparks and purple smoke arose from her horn. She hit the crystal once more, and the crystal turned black. The crystal shot out a line of shadow on the floor towards Twilight, and three black crystals quickly rose up, larger than the purple unicorn herself.
Twilight was positively afraid.
Then, Celestia, who had returned to normal and was now hovering above, shattered the crystals with light. She lowered herself and continued. "Which is why I need your help finding a way to protect it."
This was certainly NOT the kind of test she had imagined. "You want me to help protect an entire empire?"
Princess Celestia returned the crystal to its glass case. "It is, as I said, a different kind of test. But one I am certain you will pass."
Twilight's face switched from shock to sadness, and finally it stopped at determination. "How do I begin?" she declared.
Celestia approached her star pupil with a smile. "By joining Princess Cadance and Shining Armor in the Crystal Empire."
Twilight beamed. "My brother is there?!" She quickly trotted to match the white alicorn's gait.
"He is, and your Ponyville friends will join you there as well." The two approached the door, where Luna was waiting just outside. "I have every confidence you will succeed, and when you do, I'll know you are ready to move on to the next level of your studies."
Twilight looked at Luna, who now gave the purple unicorn the same grave look that she had given her sister a few minutes before. Twilight's nerves returned to her. "But what if I fail?"
"You won't," Princess Celestia assured her.
"But what if-"
Celestia put a hoof on her shoulder to assure her student once again. "You won't," she repeated, slightly shaking her head to emphasize her confidence in her student.
Twilight, still unsure, slowly walked away. "But Twilight," Celestia began, and Twilight turned back to look at the two sisters. "In the end it must be you, and you alone who ultimately assists Princess Cadance and Shining Armor in doing what needs to be done to protect the Empire." Now, a feeling of hope arose in the purple unicorn. "Do you understand?"
Twilight nodded. "Mm-hmm."
"Then go; there is no time to lose." Celestia closed the doors to the throne room.
<>--<>--<>--<>--<>
It was snowing hard as the train reached the station nearest the Crystal Empire. The doors opened, and Twilight and her friends stepped out, bracing themselves from the harsh wind. As Rarity stepped out, followed close by Spike, who was holding her things, she exclaimed, "Ha! And you all made fun of me for packing so many scarves!"
"I didn't say a word," Spike said before slipping on a patch of ice. Some of the scarves fell out, and Spike ran to get them.
Twilight and her friends looked around as best as they could in the wind and snow. Suddenly, a voice called out the purple unicorn's name through the weather. "Twilight!"
"Shining Armor?" she answered, and her brother emerged from the blizzard.
He removed his snow shades and pulled his black scarf from over his mouth. His eyes widened as he saw his sister. "Twily! you made it!" They ran to embrace each other. "We'd better get moving," he continued. There are things out here we really don't want to run into after dark."
This caused all of them to become nervous. "What kind of things?" asked Fluttershy.
Shining Armor started walking. "Let's just say the Empire isn't the only thing that's returned." As they traveled closer to the Crystal Empire, he explained further. "Something keeps trying to get in. We think it's the unicorn king who originally cursed the place."
"But Princess Celestia said I was being sent to find a way to protect the Empire." She had to shout over the howling wind. "If King Sombra can't get in, then it must already be protected."
Suddenly, a low, groaning howl overpowered the storm. The ponies all fearfully looked around, but they couldn't see anything. "That's one of the things, isn't it?!" Fluttershy worried.
Shining Armor knew exactly what that sound was. "We have to get to the Crystal Empire. NOW!" He yelled as a giant shadow abruptly rose up behind the friends. The shadow itself had purple smoke emitting from green eyes.
King Sombra.
Spike froze in fear and Shining Armor picked him up, and everypony ran. It wasn't long before Cadance's protective shield could be seen shimmering through the snow. "Almost there," Shining Armor said. He stopped, turned toward Sombra, and fired a violet bolt at the shadow. Sombra enveloped the unicorn as Twilight and her friends passed through the shield.
Twilight and her friends were panting. "Everypony okay?" she asked. Her friends nodded and verbalized that they were.
Shining Armor stumbled through the shield, his horn covered in small black crystals. Twilight ran over to him. "Oh no," she said, "Shining Armor, your horn!"
He attempted to cast a spell to remove them, but the crystals blocked his magic. He shook his head and they joined their friends at the crystal gates of the Crystal Empire. "Sparkleriffic!" exclaimed Pinkie Pie.
<>--<>--<>--<>--<>
Princess Cadance sat on a crystal throne, her horn constantly aglow, a worn and weary countenance covering her face. She hung her head as Twilight and her friends entered the room.
"Cadance!" she shouted. At once, though her eyes remained weary, her spirits lifted and she smiled wide as they ran to meet each other. They both sang their old childhood rhyme:
"Sunshine, sunshine, ladybugs awake.
Clap your hooves and do a little shake!"
They laughed, but Cadance's magic flickered, and it was obvious she was in pain. Sombra had just attacked the shield again, knowing that each hit weakened the already weary pink alicorn. "One of these days we need to get together when the fate of Equestria isn't hanging in the balance," she mused.
"Are you okay?" Twilight asked.
Shining Armor came up to his wife's side. "Cadance has been able to use her magic to spread love and light. That seems to be what is protecting it," he explained. "But she hasn't slept, barely eats. I want to help her, but my protection spell has been countered by King Sombra."
"It's all right, Shining Armor, I'm fine," she tried to reassure her husband.
"She's not fine," Shining Armor countered, and Cadance hung her head. "She can't go on like this forever; and if her magic were to fade, well, you saw what's out there waiting for that to happen."
Twilight gave a look of concern toward the window and gave Princess Cadance a reassuring look. "That's why we're here."
"Why we're ALL here," Applejack added, and the rest of them all agreed.
"Well with Cadance putting all of her strength into keeping her spell going, and me trying to keep an eye on signs of trouble in the Arctic, we haven't been able to gather much information from the crystal ponies."
"Crystal ponies?!" Rarity was so excited, she stood on her hind legs. "There are crystal ponies?!" The others stared at her with puzzled looks, and she calmed herself. "Er, please, continue."
"But we have to believe one of them knows how we can protect the Empire without having to use Cadance's magic," he finished.
Twilight got an idea. "We'll gather information from the crystal ponies and deliver it to you!"
Despite their best efforts, none of them were able to get anything out of the crystal ponies. Every time it sounded like a pony was close to telling them something relevant, they wince. As part of the curse, King Sombra made it so none of the crystal ponies would remember anything but him, and any attempts to do otherwise would cause them immense pain.
"King Sombra's spell must be why their coats aren't...crystally," she once observed to Spike.
The search was going nowhere until Applejack said she heard something about a library.
The library was a beautiful piece of architecture, with carved griffons on each side of the front stairs, and a diamond emblem on each pedestal. Twilight opened the doors, and the ponies reveled in the brilliance of it. There were three stories, with amazing shelves that were twelve feet tall, all filled with books.
Twilight stood, frozen in awe, at the sight she was now seeing. She could barely even speak.
"May I help you?" came a firm voice to their right. It was a gray mare with glasses on. Her cutie mark was a scroll.
"Yes," Twilight said as she and her friends approached the mare. "We're looking for a book." She was still lost in her little world of bliss.
"We have plenty of those," the librarian replied.
Applejack approached the mare. "We're lookin' fer a history book. Somethin' that might tell us how the Empire mighta pertected itself from danger back in th' day."
"Yes," she answered, "of course. History, history..." she muttered as she tried to remember. "Ah, yes!" she smiled.
The ponies all stood in silence for a moment. Twilight finally broke the silence. "Which is where, exactly?"
The librarian looked from side to side. "I - I can't seem to remember. I'm not sure I actually work here," she admitted.
"We'll just take a look around. I'm sure we can find it on our own."
"Let me know if you find anything." The old grey mare walked off.
Each of the friends searched the shelves in their own way; Fluttershy looked at each book one at a time, Rainbow Dash and Applejack worked to get the higher books off the shelves via kicking a ladder down the shelf, and Pinkie Pie jumped up and grabbed random books from various heights of shelves.
They were beginning to think it was a lost cause when Twilight, using her magic to float books past her into a large pile, finally found what they'd been looking for. She grabbed it and let the other books drop to the floor.
It was literally a history book of the Crystal Empire. "History of the Crystal Empire," Twilight read as she opened its pages. "I just hope it has the answers we need."