"Oh, Nightmare Moon," Twilight sighed, remembering the time when she had searched for the answers about the Mare in the Moon, "now that's a name that I haven't heard for years. I haven't thought about her since the day my friends and I defeated her in the ruined castle, wiping the darkness from her heart and returning her to who she had been before; Princess Luna."

"Wait a minute..." Nightfury exclaimed, her eyes widening as she realized exactly what Twilight had just told her, "Are you telling me that my mother, my kind and loving mother, turned into a monster that wanted to plunge the world into eternal darkness?"

"Yes, that actually happened," Twilight replied, picking Sweetie Belle up and plopping her on her back, "I had to drink a potion that would reveal something from the past to me, but when I did I saw Princess Luna give into the darkness in her heart and witnessed how Nightmare Moon was created. Princess Celestia was forced to use the Elements of Harmony on Luna, sending her to the moon for a thousand years, but, like I said, my friends and I recovered the Elements of Harmony and freed her from the darkness that had consumed her.

How did you even find out about Nightmare Moon and her plan for Eternal Darkness, when you were sealed in a raging storm that only appeared once every thousand years?"

"Oh, that would have been Thorn," Nightfury commented, though it sounded like she knew something else, "She told me that, a year after I stopped calling on her, that one of the rulers of the Darkness suddenly vanished one day and every Shadow had been searching for her ever since. Then, just a few years ago, she suddenly reappeared, wrecked beyond belief and spouting some nonsense about being defeated by six mares that channeled some powerful magic. Thorn made a note of what the Nightmare, as that was what the mare wanted to be called, said and relayed anything of importance to me whenever we met."

"Wait, so Nightmare Moon was actually a Shadow?" Twilight asked, realizing that it was a crazy idea that only Princess Luna could actually verify if they asked her.

"It sounds like it," Nightfury replied, shaking her head as they started out of the forest, "Thorn made a note of Nightmare's sister being rather angry the moment she vanished, which could have been the moment that my mother accidentally called the Shadow into our world and, more importantly, into her body. Whoever this second ruler of the Darkness is Thorn either wasn't able to acquire the information and share it with me, or she's unable to do so without tipping the other mare off. I have the feeling that I haven't seen or heard the last of the Shadow's activity for quite some time."

The more that Twilight thought about Thorn, the strange Shadow that Nightfury had befriended over a thousand years ago, the more she wondered what her role was in the world known as the Darkness. It appeared that Thorn was just like Twilight in a sense, which was that they both enjoyed studying and learning about magic, which is what lead Nightfury to bond with the Shadow. Thorn had seemed excited when she had been summoned for the first time in a thousand years, but then had remembered her duties to Nightfury and told her all about Nightmare Moon escaping from her world.

Twilight wasn't sure that she could trust the Shadow just yet, but she trusted Nightfury to keep the Shadow in line and that was enough for her stressed mind to handle at the moment.

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It took them an hour to get back to Ponyville, but when they reached Rarity's Boutique Twilight had to explain to Rarity why Sweetie Belle had been with her that afternoon and why she had been exhausted. She wasn't too pleased that they didn't tell her that they were taking Sweetie with them, but then she got mad at Twilight when she heard that they let a Shadow into her little sister's body. Rarity didn't know what a Shadow was, nor did she care what they were, but she insisted that something terrible could have happened to her sister during the entire thing. Eventually Rarity huffed in their faces and took her sister inside, leaving Twilight and Nightfury to their own devices for the remainder of the afternoon.

Instead of returning to the castle Nightfury inquired where Canterlot had been built, causing Twilight to smile and point to the east, right at the city that was built on the side of a mountain. Before Twilight could inquire as to what Nightfury wanted to look for in Canterlot she took off, leaving Twilight behind and allowing her to do whatever she wanted. Instead of following the other alicorn Twilight simply sighed and moved back to her castle, where she would find Spike and have him send a letter to the Princesses that Nightfury was on her way to Canterlot.

There were multiple reasons for Nightfury heading to the city of Canterlot for the first time; she wanted to explore the place her aunt created, she needed to speak with her mother about the Nightmare, and she needed to find the other two Sigils and make sure they were both still safe. Thorn had commented that the other leader of the Shadows was trying to discover where they were located so she could gather them at her leisure, though Nightfury knew what the mysterious mare was planning. The leader of the Shadows was trying to open a gateway between the Darkness and Equestria, allowing them access to their world through a hole that not even she could fix.

Nightfury wasn't willing to risk the safety of their world, which is why she needed to make sure that the Sigils of Earth and Water were safe and sound.

With as fast as she flew she reached Canterlot within an hour, but as she landed outside the castle she realized that she had absolutely no idea where her aunt could have hidden the two Sigils. The guards, two white coated pegasi, stared at her as her eyes darting all over the place, looking around for the possible locations where the Sigils could be hidden. It was then that she recalled that Crimson mentioned that he and Twilight had come to Canterlot within the last few days had had discovered where they were located, but she really wished he had told her where. After a few minutes of debating between her options she spied what she assumed was the Royal Library, which she suspected was the best place to start her search.

She quickly made her way to the library, entering the hallway before she was forced to search for the opening that would lead her right into the library. As she drew closer to the library she noticed that her Sigil started to glow, telling her that she was closer to the first Sigil then she had thought she was. When Nightfury reached the library she passed through the opening and immediately began her search, her eyes scanning the room, the shelves, and even the carpet for any hidden compartments. She noticed the hourglass after five minutes of searching, but when she looked at it she noticed an emerald color appear in the sands.

She had found the Sigil of Earth, but now she needed to find the Sigil of Water and suspected that it would be even harder to find than the one before her.

"Nightfury?" a voice behind her said, causing her to turn around and find her mother standing by the doorway, "What are you doing in Canterlot? I thought you would have been enjoying your freedom and making friends with the residents of Ponyville."

"Mother?" Nightfury gasp, surprised that she had been found out so quickly, "How did you know I was here?"

"Well, the guards saw you heading this way," Luna remarked, draping a wing over her daughter, "so when they told me you were here I knew you'd be doing the same thing that Crimson did when he came to Canterlot; searching for the Sigils. Also, Twilight Sparkle sent my sister and I a letter saying that you were on your way here, so I just ordered the guards to tell me the moment you arrived. But what would possess you to leave Ponyville and come here, so soon after returning to Equestrua?"

"Well..." Nightfury said, hoping that her mother remembered her assistant, "Twilight asked me what the Darkness was and I took her into the Everfree Forest, where I showed her one of the denizens of the world she didn't know even existed. I summoned Thorn for the first time in the last thousand years and conversed with her, though she shared some disturbing things with me that I needed to check up on. I was just checking the locations of the other two Sigils, Earth and Water, to be sure that they were both safe and sound and that they hadn't been taken."

"Sounds like you need to check on the Sigil of Water then," Luna replied, though she saw that there was something else in her daughter's eyes, "but there's something else you need to ask me."

"I heard about Nightmare Moon," Nightfury said, turning to face her mother, "I heard that, shortly after Crimson and I disappeared, you lashed out at Aunt Celestia and became a creature bent on blocking out the sun. Mother, Twilight and the others may not know the whole truth about the ordeal, but I managed to piece enough together to realize what happened back then. You broke the Veil for a moment, just a brief moment, and allowed a Shadow to take control of your body, twisting you into somepony that was completely different from who you were. How could you do something like that?"

Nightfury looked like she was a little panicked, as if the thought of her mother becoming something different was something that she had never thought of or even considered. Luna couldn't blame her, she didn't like what happened anymore than her daughter did.

"I...I was depressed," Luna sighed, knowing that this topic would have come up once her daughter had summoned her assistant again, "you were gone, Crimson had all but vanished from the face of Equestria, and ponies began to ignore my beautiful night so much that it made me angry at my own sister. When I finally spoke with her I let my fury get the better of me and I could feel the Veil that you protected, something I was barely aware of if you hadn't spoken about it, open for a moment. The Nightmare took over my body and my mind, though the next thing I remember after that ordeal was waking up in the ruined castle, my mind and body freed at long last.

I can only assume that the Nightmare had been blasted back to the Darkness by the Elements of Harmony, where she belonged and where she would stay if I could help it. After I regained my powers I finally spoke with my dear sister and told her about the Veil, explaining what had happened to me when the Nightmare took over. She said that she knew what had happened, as she found your journal detailing the Darkness and all the Shadows that you and Thorn already knew about. She forgave me for what happened, though she did return your journal to me and I have kept it in my room every since, waiting for you to return."

"Can I check anyway?" Nightfury asked, meaning a brief magical scan for any lingering trace of the Shadows, "I just want to be sure that the Nightmare didn't leave any nasty surprises."

Luna nodded and held her head down, letting her daughter's horn light up as she made sure that there was nothing lingering in her magic or her mind. She recognized the spell, as they had used it to great effect to hunt down those tainted by the Shadows before they departed them back to their world. If there was really anything lingering in her mind or body Nightfury would find it, where she would immediately get rid of the taint and free her once more.

"How is Thorn doing anyway?" Luna asked, wondering what the little Shadow was up to, "Last I heard of her she was warning us of the potential war with the dragons, which sparked the Dragon Wars of our history."

"She's fine," Nightfury replied, her horn dying down and letting out a sigh, just glad that her mother was safe and sound from the Shadow's taint, "she commented that she hadn't been summoned in the last thousand years and asked who she was going to be sharing a body with so she could perform her duties again. I don't know who would be willing to let a Shadow into their body, so there's no telling when I'll be able to call on her again."

"Come, let's leave the library and show you the fourth Sigil," Luna said, beckoning for her daughter to join her as she moved towards the hallway, "I'm sure that you are more interested in finding it then speaking about the Darkness and all the Shadows that reside in that world. I'm positive that we can come up with a plan to let your assistant come back into our world again."

Nightfury nodded and the two of them made their way down the hallways, passing by quite the number of guards as they went, before they passed the throne room. Luna made sure to tell her daughter that Celestia was still busy with the evening court, just like she had done with Crimson when he had visited Canterlot earlier. Nightfury seemed more interested in learning about the court at the moment, but when Luna reminded her of the fourth Sigil she sighed and followed after her mother. Luna, however, promised her that she would let her sit in one night while she performed her court duties, so she could see what being a princess was all about these days.

Eventually Luna led them down the same hallway that contained the hidden gateway, where they approached the glowing lights and followed the sound of running water. Nightfury rubbed her eyes a bit before she looked out at the lake that she found themselves standing in front of, wondering if this was where the Sigil was located. The Sigil of Air glowed for a moment before dying down, though the center of the lake began to glow with a sapphire hue, telling her that the last Sigil was right in front of her.

"She took Crimson's suggestions to heart," Nightfury commented, realizing what the sands and the water meant, "Aunt Celestia hide both of the Sigils where nopony would ever think to look for them."

"That she did," Luna said, draping her wing over her daughter again, "Now that we've gotten all of the Sigil business out of the way I have some things that I need to give back to you, things that my sister rescued from the ruined castle before she departed. I'm sure there's a couple of items that you'd love to have in your possession again."

Nightfury smiled and pressed her head against her mother, enjoying the moment they were sharing as she stared out at the lake and ignored the fact that the Sigil of Water rested before her.

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Rarity's Boutique, quiet save for the noise of Rarity's tools that worked whenever she was working on an order for dresses, the occasional hat, or even a winter suit. Thanks to the two parties she had attended over the last week she was a few orders behind, but she intended to get all her work done in time for the buyers to pick them up. When Twilight had returned with her little sister Rarity had gently put Sweetie Belle to rest in her room before getting to her work, knowing that her sister would be up and about in an hour or two. She figured that she could get some work done before allowing Sweetie to go hang out with her friends, if that was what she wanted to do with the rest of her afternoon.

Sweetie Belle shifted in her bed while her sister worked, squirming about as her peaceful dream suddenly shifted into a nightmare that seized her mind. She moaned as she felt her body start to go cold, but then started to violently cough as something smoky entered her mouth and forced itself down her throat. She thought that it felt exactly like what had happened in the summoning circle that Nightfury had used, but instead of no pain this one was forcing it upon her. Eventually Sweetie Belle sighed and the darkness coursed through her body, wrapping itself around her as she stopped squirming and coughing.

Her eyes snapped open, revealing their bright red color, and she looked down at her coat, watching it turn into the dull grey color it had been earlier that day.

"Hehehehehe," Sweetie chuckled, a grin appearing on her face before she cracked her mouth open, "Ha ha ha ha ha!"