"Believe me, Mordrid, if I never felt it necessary to come to this horrible place, I wouldn't have," Celestia growled.

"Yes, I can't imagine most ponies would be interested in a social call around here. I mean, the good curtains aren't even up! But, there's no reason we can't at least try," the abomination quipped. "So, Celestia, how are the folks?"

Mordrid grinned widely at the question, and the Princess sneered in outrage. Twilight noticed the look on her face and blinked in surprise. It was something she never saw her mentor ever express before: Hatred. She kept quiet as Celestia had requested earlier, but intended to talk to her after they had finally left. Surely what was about to transpire was going to leave her with even more questions that she wanted answered.

"I'm sorry, was it something I said?"

"You're still a monster," Celestia said in disgust.

"Hm, and here I thought time healed all wounds, and we both know how much time you've had, Celestia. Ah well. Seems some ponies just can't forgive and forget, now can they?" he asked, his voice dripping with sarcasm.

It was obvious to Twilight now that these two had a history, but the Princess never spoke about this freakish alicorn before. She recalled the nervousness and sorrow in Her Majesty's voice from earlier in the day. She spoke of some things she wished she could forget. What exactly happened? The unicorn put it on her mental checklist to ask about later, if the Princess would be willing to talk about it.

"A million years could pass and I still would never forgive you for what you did."

"That wounds me deeply, my dear," Mordrid jested, dramatically pressing a hoof to his chest. "But I digress. I suppose we should skip the small talk and get right down to business, yes?"

"The sooner we can end this visit, the better. Your very name sickens me, so you can imagine what being in the same room with you again is like," Celestia spat. "I'm sure you know why we're here anyway."

"Of course I do! There isn't exactly much for one to do around here except watch the living." Mordrid put a hoof to his chin and continued his ridicule. "Although, I'm not exactly what you would call dead. Care to try again just for old time's sake, Celestia?"

The Princess glared. The fiery alicorn shrugged and went back to his rambling. "Hmph. You were so much more fun before you chained me here. I will admit that there simply aren't any creatures quite as divine and.. enthusiastic.. as you once were, but that's to be expected in a place like this."

Celestia cut Mordrid off, trying to speed things along. "What do you hope to accomplish by corrupting Pinkie Pie's spirit and turning her into a killer? How is she even able to escape this place?"

"Such a stick in the mud! Anyway, I didn't do a thing to her. When she died, she was quite angry with you and the others," he said, pointing to Twilight. She shrunk back and averted her gaze. "That anger stayed with her after she moved on, and when spirits are in such a state, complete with feelings of revenge and the like, they come here. She felt betrayed by you all, and can you blame her? It was your negligence and complete disregard of her opinion that led to her getting killed! I'd be pissed too."

"B-But, we were her friends! It was an accident!"

"Those kinds of things don't really matter in the afterlife. I would be a little more familiar with the subject than you, y'know. As far as her getting out of here," he paused and looked away, extremely annoyed, "I haven't done that either."

"Then what's going on?"

He sighed, frowning. "I honestly have no idea with that one. She's.. unusual, and if I have to say that, then, yeah, there's something extremely wrong."

Celestia's eyes shot wide open. "She's been getting out on her own?"

"I'm afraid so, and whether you believe it or not, that's bad news for the both of us."

"How do you mean?"

"Well, it's obvious how an angry, vengeful, murderous, dream-walking ghost could be bad for you and your little subjects," Mordrid mocked, "but it's not exactly great for me either, which would also make it not great for you. Again."

The royal mare lifted an eyebrow. "Explain."

"I don't mind being the Lord of Tartarus, I really don't. But, I rule through my immense power and through fear. Even though I'm permanently bound to this place and unable to open the gates thanks to you – unless of course, you'd like to undo the spell and we can try and patch things up?" he asked derisively. Celestia responded with an irritated stare. "No? Well, I tried. Anyway, not all my minions are brutes and imbeciles. If they see that a little pink pony is able to make me look like a fool and leave whenever she wants, they may see me as an inept ruler and try to overthrow me."

The Princess glared at Mordrid and growled under her breath, "You're breaking my heart."

"Oh, it's not quite that simple. As I was saying, there are some of them that are rather cunning and fairly intelligent, and they've wanted to get back outside and spread chaos again for a while now. Now, If I was ever freed from my bonds, mark my words, I would open the door and let my armies loose on your world again." A large, toothy grin spread across his face.

The smile faded away almost instantaneously. "But, if some of these lesser demons figured a way out of here on their own, they'd rampage across Equestria themselves, and I'm not going to let some peons take credit for all the work I've been putting into readying my troops. I like my seat. It's rather comfy once you get used to it," he said, patting the seat of the skull throne behind him. "So, yes, only because of the fear I inflict upon these creatures is your home and everything you know and love still even around. Are you willing to put them all at risk just because I make your stomach turn?"

After a moment of contemplative silence by the Princess and a knowing smirk by Mordrid, coupled with his breathing on a hoof and wiping it clean on his coat, she sighed. "Fine. What can we do to help?"

He set his hoof down and blinked at her in disbelief. "You're serious? You haven't thought of it?"

"If it has anything to do with you in any way, then no, I haven't thought of it," Celestia retorted angrily. "Why don't you tell me what you're referring to so we can leave?"

Mordrid rolled his eyes and smirked. "Oh, very well. I know you found my notes long ago and used them to chain me here. Maybe it's time you whipped out that dusty old book again. I'm willing to bet you still have it. You were never the kind to discard antiquity."

"How am I supposed to cast those spells on her when she isn't even in this plane of existence?" the Princess asked.

He vanished and reappeared next to Twilight, causing her to jump in surprise. She slinked away as a hoof caressed her cheek. "Not my concern. I just suggest you figure out a way quickly, if not for my sake, but the sake of your precious little followers like this lovely little flower here. Goodness knows you wouldn't want any more misery and death to befall them."

In a burst of magic, he popped himself back to his throne and smiled wryly at them. Celestia wrapped a comforting wing around her faithful student and glared at her old enemy. "Don't you touch her," she scowled.

"Oh, come on. It's not like I infected her with anything. It was just a harmless gesture! If I didn't know any better, I'd detect a hint of jealousy in your voice. Now, you really should be off. You've got a pink nuisance to deal with," Mordrid said, waving them away. With a final, loathsome look at their host, the mares turned around and began to leave.

"Oh, and Celestia?"

She craned her head back and glared.

"Visit again soon!" He wiggled his eyebrows in mock seduction.

Snorting, she turned back and continued her exit with Twilight right beside her. Mordrid waved goodbye as they walked away. He chuckled to himself once they were out of sight and burst into flames, vanishing into thin air.

As Celestia and Twilight entered one of the closest tunnels that lead back to the entrance of Tartarus, she looked at one of the demonic skeletons laying on the ground and got an idea. Glancing over the bones, she spotted three of the larger ones and picked them up with her magic. The pair continued ahead and after about fifteen more minutes of walking, they came across the gate that led between worlds. Reciting the chant from before, the doors opened, spewing forth their bright glow. Twilight was at a loss as to where the light came from, considering the cave outside was as black as night.

Once they left the wretched world, Celestia sealed the gate behind them and lit the room with her horn. They exited the large chamber where the door to the underworld was, and once outside it, the Princess marched up to the vigilant, three-headed guardian. Cerberus had been scratching behind one of his six ears and set his leg down upon seeing them. Those same ears perked up when three large, juicy bones levitated in front of him.

"Thank you, Cerberus. Please accept these tokens of my appreciation," the Princess said.

With tongues happily hanging out and drool cascading, he greedily snatched the bones out of the air and flopped to the ground, gnawing hungrily on them. Satisfied, Celestia pressed on toward the distant mouth of the cave. Twilight watched Cerberus tearing into the bones for a moment before deciding to catch up with her teacher.

The fur on Twilight's neck stood on end as they finally reached the entrance to the cave. She shivered. After witnessing the horrors Tartarus had inside it, finding herself in the Everfree Forest, with or without her teacher by her side, was a welcome change. Even the Princess sighed a breath of relief once they were outside, but she looked as if she was about to cry. Twilight couldn't begin to imagine what must have been going through Celestia's mind after seeing that Mordrid pony. She needed to know. Maybe she could help.

"Princess, what.. who was that? How did you know him? I just never pictured you of all ponies to know somepony like that."

Her head fell as did her spirits. She knew Twilight was going to want to know everything, so there no longer a point in keeping it from her.

"He wasn't always like that. A long, long time ago, he.. was actually somepony very special to me."

Twilight's jaw nearly hit the ground. "Wha.. how? What happened?"

Celestia walked down the path leading away from the cave and continued her tale, her student beside her. "It was roughly forty-eight hundred years ago. The ruins of the castle not far from here, where you and your friends found the Elements of Harmony, used to be as beautiful and alive as Canterlot is now. It was where my.. my father and mother ruled over Equestria when Luna and I were still young. Young for us, at least.

"Mordrid was a powerful mage, one of my father's finest magic users. He was a chancellor and frequently visited foreign lands as one of our representatives. But he loved to study magic more than anything, just as you do now. He'd return from many of his trips with books to read and spells to learn.

"I think it was his thirst for knowledge that originally drew me to him. He was always so eager about magic, it was so much fun to be with him and listen to him talk about what he had seen and learned. It didn't hurt that he was.. well, rather charming and handsome. At the time, his mane was midnight black with some hints of grays and whites streaked through. Very regal, very wise looking. We began to see each other behind my parents' backs. I knew they would never see him the same way I did, but I didn't care.

"After he returned from one particular excursion, he seemed a changed pony. He was suddenly very distant and we didn't spend much time together. Whenever I tried to ask him what was wrong, he would tell me not to worry, that there was something he needed to do to fix this thing he never wanted to mention."

The Princess lifted a low-hanging branch out of their way and lit her horn as they entered a dark part of the forest. Her story went on.

"Finally, I convinced him to tell me. He came across a tome with spells almost as ancient as the world. The spells described summoning demons and gates to Tartarus and other such horrible things. He worried about the possibility that these incantations may have already been done at some point somewhere and suggested to my parents that we summon a gate and open it so that our armies could go in and destroy whatever may be waiting for us.

"They dismissed his idea as unnecessary.. crazy. They argued that as long as nothing was going on there, there was no need to worry. My father also told him to stay away from me. Apparently, he had been aware of our affair for a while and this gave him the perfect reason to break us off. Despite his protests, I still tried to see him when I could, but after my father tried to break us up, Mordrid suddenly became extremely cold and distant to everypony and everything. He kept insisting they were wrong and being short-sighted. I tried to console him, but nothing seemed to work."

Celestia closed her eyes and tried to hold back tears that were forming. Reviving memories she wanted to remain forgotten was taking its toll on her. Twilight reasoned that whatever they felt for each other so long ago must have been heartfelt and genuine enough to have such a lasting impression.

"A few weeks passed and one day, I went to see him, but he wasn't anywhere to be found. I checked his chambers to see if there was a note or something telling of where he may be. He couldn't have been away on royal business anywhere; Father didn't assign him any tasks. I found the tome open to a series of spells that I recalled him speaking of. He must have been studying and memorizing them. I looked through the book and found so many terrible spells. I tried not to look for long, lest I be tempted to learn them myself.

"Not two hours later, there was a rumbling that shook the palace. It felt like it came from the southwest. I learned later that it came from that very cave we were just in. Within the hour, an army of foul creatures descended upon the castle, destroying anything they could. Our armies fought bravely, but the battle ended up dragging on for days.

"Later that first day, Mordrid appeared before my parents, myself, and my sister. He looked like how you saw him earlier. I was.. horrified. He told us that he wanted to show my father and mother exactly why they should have listened to him, so he unleashed the armies of Tartarus into our world. Just to prove a point.

"I asked him what happened to his appearance. He told of a spell he found in that cursed book that could grant you immeasurable power, but it had a cost. He gave the evil spirits the spell summoned his soul in exchange for that power, and with it, he was given those skeletal wings and his beautiful mane and tail turned into flames that wouldn't burn him. Everything I knew and loved about Mordrid had been changed into this.. thing.

"During the days and nights of fighting, I retreated to his room again and looked through that tome, trying to find something that could reverse things. I found nothing, but I did find another spell that caught my attention. I.. I-I didn't want to do it. But I had no choice. He would have destroyed everything!"

Celestia stopped short and fell to her haunches. She started to cry, even as the worst had yet to have come.

"Princess?"

Sniffling and wiping her snout, she resumed the story, trying not to let her emotions get the best of her again. "The spell chained the victim to Tartarus permanently, but it required two things. First, an object precious to the one who you sought to use it again, and a sacrifice by the user themselves. Another cost. It never specified how long it would take for any of these prices to be paid. All it said was that it could be five minutes, five days, five years.. anything really. I found a particular totem of his in his chambers that he used with many of his more powerful spells, grabbed the book and sought out my parents.

"I learned from one of the soldiers fighting for us that they decided to join the frey. They were about to finish pushing Mordrid into Tartarus. They were thrilled to see that I found the words used to open and seal the gate and figured they'd use the book against him. They were also happy to see me there so they could show me what kind of a monster Mordrid really was. I used the binding enchantment against him, but right as he was being pulled into that place, he lashed out and.. a-and.. "

Hot tears cascaded down her cheeks. Twilight's stomach turned as she shared her pain. She never thought she would ever see the Princess in such a state. She rested a hoof on her royal shoulder, trying to comfort her.

"I'm here. What happened?"

"He.. he killed them! He took my mother and father away!"

It was too much. Her head fell slowly into her folded legs and hid from sight. She wept loudly in the dark heart of the forest. If a feral beast had heard her and silenced her tears right then and there, it would have been considered a blessing to her. Twilight's mouth hung agape as she took in the devastating news.

"Princess, I.. I'm so sorry. I never knew."

Celestia gazed at her student and caressed her mane. She tried as best she could to smile warmly at Twilight's concern.

"It's alright, my student. I.. don't like talking about it."

She sniffled as the last of her tears finally fell from her eyes. A handkerchief popped into existence, surrounded by a purple glow. They exchanged a soft glance and the Princess smiled, took hold of the cloth and wiped her cheeks dry.

"Right there in that cave, as soon as I shackled Mordrid to that place, I figured out that.. that they were the sacrifice. I'll never forgive him for it."

"I wouldn't either."

The alicorn sighed and rose to her hooves after a moment of quiet mourning and they began their trek home again. Celestia wasn't quite finished and spoke of the tragic events more.

"Even after he was gone, things never completely recovered. The castle was destroyed, so we had to relocate. We eventually constructed Canterlot as it is today.

"But, the forest suffered as well. Despite our best efforts, a few demons escaped imprisonment. Our armies caught up with them eventually and slew them, but their influence spread and corrupted everything. The trees, the flowers, the animals.. it even feels like the air was affected. Creatures like the timberwolves, the Ursas, the cockatrices, they all exist because of the demonic infection.

"Nothing we did to try and reverse the effects worked either. It's been so many centuries that the influence has become a permanent part of things here. I cast a spell over the forest long ago to at least stop the spread. I assume that your zebra friend who lives here was aware of the corruption and cast a spell that protects her from it as well."

They traveled for a few minutes in quiet contemplation. The last bits of sunlight snuck through the overgrowth as the end of the day approached. They must have been in there longer than they thought. Either that or time doesn't move at the same speed in Tartarus. Twilight finally broke the silence.

"I assume that we're going to use those same spells against Pinkie if we can?"

The alicorn nodded firmly. "That seems to be the only real course of action, provided they can work against her. Mordrid was correct, though. I do still have those notes of his. They're hidden in a secret chamber in the Starswirl the Bearded wing in the Canterlot archives. Up until now, only myself and Luna knew of their existence. Now, you will as well."

"Then we have to hurry. Even though a part of me still cares about her, she needs to be stopped."