In the far western deserts of Equestria, farther than even the most isolated Buffalo tribe, there exists a small compound surrounded by fences and warning signs. A single building constructed of heavy stone and set deep in the ground was bustling with activity in the otherwise lifeless land known only as 'The Wastelands'.

“Okay, Princess. I think we're ready!” Twilight Sparkle said enthusiastically. Behind her, Princess Celestia gave a silent nod for the genius unicorn to proceed. Twilight approached the narrow slits in the thick stone walls of the Unusual Energy Research Facility. The half dozen other unicorns in the room, as well as Celestia's two personal Pegasus guards, tensed as her horn began to glow. The Princess herself remained relaxed, but her interest was visibly peaked.

Many miles away, too far for most of the ponies present to actually see, rested a 100 hoof tall tower. At the top of the tower rested a 10 hoof wide sphere covered in magical runes. Through her magic, Twilight was able to see the sphere slowly begin to glow a light purple as she pumped her own magic into the matrix.

Quickly, Twilight cut off the flow of her magic into the sphere and to the delight of the lavender unicorn, the sphere continued to glow. In fact, the intensity of the light began to grow exponentially. Soon, the small orb grew so bright the ponies in the hardened bunker were forced to look away. Celestia, Twilight, and the unicorn mages donned special, protective goggles Twilight had designed for this exact moment.

The glow quickly grew to unbearable levels. Then, a bright flash illuminated the entire landscape. For a fraction of a second, shadows ceased to exist. The feeling of standing in front of the sun came and went in an instant. Then a massive explosion rocked the earth below their hooves. A furious roar thundered in the ponies' ears.

The shock wave of the explosion rushed outwards, obliterating anything and everything in its path. A quarter of a second of calm was followed by the superheated air rushing back towards the epicenter of the explosion. Anything that had survived the initial blast wave was erased. Seconds after it began, the destruction was over. In its wake a titanic mushroom cloud rose high into the Equestrian sky.

Miles away, the observation building was filled with cheers by the ponies present. Many patted Twilight on the back for her successful experiment. Bottles of sparkling sarsaparilla were opened in celebration. Twilight was practically bouncing in elation. Months and months of preparation and research had led to this moment which was to be her crowning achievement.

With a smile so bright it challenged the sun itself, Twilight looked up at her mentor. Celestia looked down at Twilight with pride in her eyes and a loving smile. “Most wonderful, Twilight. I am so glad your experiment was a success.” Twilight's smile somehow managed to brighten even more.

“Oh Princess! Do you know what this means? It could have so many uses! I can't.....I can't even begin to imagine all the ways this new energy will be able to help Equestria!” Celestia nodded and gave her student a gentle nuzzle.

“You have accomplished a great feat here today. I am very proud of you, Twilight.” Twilight's smile threatened to snap her face in two at the compliment. Celestia raised her head to look at the still-rising mushroom cloud. “But, I'm afraid Royal duty calls. I must return to Canterlot, and I am sure you will find yourself busy in the coming days.”

Twilight seemed to wilt slightly but rapidly nodded. “Oh yes. There is so much data that will have to be analyzed! We have to go over the atmospheric readings, test for residual energy, completely re-survey the local magical field, and-”

“Yes, yes and I am sure you will enjoy every moment,” Celestia interrupted with a knowing smile. Twilight's cheeks reddened and she nodded sheepishly. “When you find the time, please do come visit. I have missed you these past months, and I know Luna feels likewise.” At the mention of the Princess of the Night, Twilight's cheeks became as red as a freshly picked apple. Celestia pretended not to notice to spare her student any further embarrassment.

She stepped away from the other ponies in the room and motioned for her two personal guards to step closer. Celestia's horn began to glow as a field of magic surrounded her and the two Pegasi beside her. “Farewell for now, Twilight.”

There was a flash of light and Celestia and her guards reappeared in the Throne Room of Canterlot Castle. “You are dismissed. Please have the kitchen send a small snack up to my private chambers.”

“Yes, You Majesty.” Both the guards bowed and trotted off. Celestia yawned and began the short trip to her private chambers, occasionally nodding at a stray guard or staff pony. The tired Alicorn arrived quickly and smiled at the two gray unicorn guards stationed beside her door.

“Good evening Stone Wall, Razor Edge. How goes the evening?” She asked lightly. The guards' horns lit up with golden magic as they opened her twin doors for her.

“Very well, You Majesty. Fortunately Princess Luna has yet to attempt another prank this night. I believe your last.....retaliation has given her pause.” Celestia giggled, thinking back. It had taken weeks for Luna to get the last of the gum from her coat. She was still searching for the method Celestia had used to make the 'infernal sticking substance' as she called it, magic resistant.

“Oh, yes, but I seriously doubt she had given up for long.” Celestia yawned again and was reminded of just how tired she felt. “Good night, my little ponies.” The guards bowed and Celestia gently closed the door behind herself.

She walked to her dresser and cast off her regalia. She levitated a half dozen brushed and ran them through her mane and across her coat. While her ethereal mane wouldn't get tangled into knots, it was still a nice relief from the stresses of ruling. Celestia lost track of how long she had been brushing herself when she cracked open her eye to look at herself in the mirror.

As always her coat was a polished white, her mane a subdued yet still radiant menagerie of colors. Her horn was polished to a fine shine, and the aura of magic around it matched the candles around her bed which illuminated the creature reclining on the soft white sheets of her BED?

Celestia whipped around, dropping her brushes and taking up a defensive stance. Her horn glowed with a surge of magical energy as she pointed it directly at the strange creature that had made a place for itself at the center of her bed.

The creature was unusually shaped; it had only two legs and a pair of arms, currently crrossed behind its head and resting on the pillow pile at the head of her bed. Its body was mostly hairless except for a small patch atop its head. It wore a loose black cloak that covered its torso, as well as strange leggings. Its arms were visible and what skin she could see was pale. Its hooves were strangely shaped and covered in shiny black gloves.

“I was wondering how long it would take you to notice me. You just looked so relaxed I didn't have it in me to disturb you.” Its voice was light and obviously male. Amusement shone in its eyes. Regardless, Celestia maintained her guard. She had never seen such a creature, and the last time a new creature had shown itself it had turned out to be the embodiment of Chaos, Discord.

“Who are you? And how did you get into my chambers?” The creature waved a hand and snorted.

“If you're asking how I got past those hilariously weak security charms you placed on this room, it wasn't that hard. If you're asking in a more literal sense, I used the door.” The creature pointed at the still-open door to her balcony. Celestia scowled. Her most powerful charms protected her chambers, surpassed only by the enchantments placed around the Elements of Harmony.

“I'll ask again, and this time I command you to tell me. Who are you?” Celestia ordered in a steely voice.

The creature seemed to think for a second before hopping offer her bed and strolling around the room. “You know, that's a very interesting question. 'Who are you?'. Quite the question......” The creature glanced through the various painting Celestia kept on her walls, both of places and ponies long since gone.

“THOU SHALL ANSWER OUR QUESTION!” Celestia roared, using the Royal Canterlot voice for the first time in centuries. The creature winced at the volume.

“Oh calm down, you'll live longer. You know stress is one of the leading causes of death.” The creature chuckled. “Though for the likes of us, I doubt that's an issue.”

Fed up, Celestia fired a magical blast at the intruder. Not enough to do serious damage, but enough to convey her annoyance. The blast passed completely through the creature who seemed to turn to vapor at the contact. The blast slammed into a lamp which was completely vaporized. The smoke swirled and reformed the creature in another part of the room, this time looking at a set of neck rings presented from the distant Zebra Kingdoms.

“Was that really necessary?” Seeing Celestia prepare another blast, the creature raised its hand. “Alright, alright. I'll answer your questions. I wouldn't want to be responsible for destroying all these nice little trinkets.”

Celestia dissipated the spell she had been preparing but maintained the magical charge in her horn. “Good. Now, as I've asked before, who are you? I have never before seen a creature such as yourself.”

“Creature?” The creature looked down at himself and shrugged. “Okay, maybe a little. I could use a shave, I suppose.” Celestia grunted in annoyance. “Oh right. Well, I wasn't lying earlier. I'm afraid in my case 'Who are you' is a rather interesting question.” The creature picked up an apple from a fruit bowl, sniffed it, and placed it back in its place.

“Well, it depends on who you ask. What I am has a lot of different names. Some would call me a god or a demon. Others might call me a ghost. My own people might called me an angel or something along those lines, though I never got the equipment to go along with it.” The creature pointed at Celestia's wings.

“There's been a lot. Some stranger than others. One race actually called me 'The Ice Cream Man'. Even I'm not sure how that came about. I guess something got lost in translation.” The creature laughed, and then its face became serious. Sad, even.

“Doesn't help I've forgotten my real name. I try to remember, but it was so long ago......” The creature's eyes spaced out. It was a look Celestia recognized. She and Luna often wore it when reminiscing over the thousands of years they had lived.

“You are immortal.” It wasn't a question. The creature chuckled and nodded.

“Yes, and that is part of why I'm here. The rest has to do with the name I've been using for the past eight centuries or so. 'The Harbinger'.” Celestia's eyes widened slightly and her muscles tensed.

“I get that reaction a lot. Still, I thing the name's worth it. It just sounds so.....I don't know......theatrical, I guess.” The creature shrugged.

“If you call yourself 'The Harbinger', then it would stand you are here to deliver a warning.” The Harbinger nodded, so Celestia pressed on. “What are you here to warn us about?”

The Harbinger shook his head. “Not 'us' Celestia. You.” he pointed at her. “I'm here to warn you.” Celestia tilted her head in confusion.

“Very well. Warn me of what?” The Harbinger picked up a small notepad and a quill from Celestia's desk and began to draw. Celestia was unable to see what it was he was drawing, and he continued.

“That...little 'experiment' as you called it. The one you went to earlier today. That. That's why I'm here.” The Harbinger's answer was not at all what Celestia had been expecting. The Sun Princess allowed the magic in her horn to dissipate, curious as to The Harbinger's meaning.

“The experiment? It was nothing more than a test of new magical rune styles.” The Harbinger shook his head, not looking up from his drawing.

“No, no it wasn't. Well....maybe it was. For now, at least. Let me guess; it was a method of using magic to super-condense some kind of heavy metal to release energy.” Celestia was taken aback, and nodded.

“Right. Thought so. My people called it nuclear energy. Eventually, it leads to nuclear weapons. That's where I come in.”

“Wait, that makes no sense whatsoever. Assuming the magic is able to be harnessed for practical uses, it would be used as an energy source.” The Harbinger snorted.

“You have no idea how many times I've heard that line. 'Oh no, we won't use it for weapons.' 'We need the energy.'. 'We are a peaceful people.' My favorite one though has to be 'But we need better weapons to defend ourselves!'” The Harbinger shook his head sadly.

“No matter how it starts, it always ends the same. Would you like to see?” He asked. Celestia nodded. The Harbinger tossed the quill aside and turned the notepad to face the Princess.

Celestia gasped. She took an involuntary step back as tears filled her eyes. The image, despite the haste in which it was drawn, clearly showed Canterlot. Though not the Canterlot she recognized. The picture was of Canterlot in ruins. Every building was shattered. Barely a brick lay upon another and massive columns of smoke rose over what was left of her city.

But what truly struck the Princess' heart was the hundreds, thousands of dead ponies lying on the mountain road that led away from her city. They had all clearly died running. The closer to the city, the more charred and blackened were their corpses.

In the foreground, clear for her to see, a tiny filly lay dead in the arms of her parents who had apparently died trying to shield the poor pony from whatever danger had killed them. Celestia's rear legs gave out. The Harbinger allowed Celestia to stare for a few moments before walking to the edge of her bed and sitting down.

He tossed the notepad behind himself to the center of her bed. All humor was now gone from his face. “That, Princess, is what lies in store for your ponies. I don't know how and I don't know when. What I do know is this; if you keep up your current course of action, then that-” he pointed out the window towards the city, “will all be destroyed. Not just Canterlot, not just Equestria. All of it.”

Celestia was still in shock at what she had seen. The image of the filly, face locked in an eternal scream.“.....how.....” She couldn't finish her sentence. However the Harbinger already knew what she was asking, having been asked it many times before.

“It doesn't matter how. Even if I knew and I told you and you managed to avoid it, the result would be the same. Circumstances would change but you still end up there." To drive his point home he nudged the drawing towards Celestia, who moved back an equal distance.

"Destroy the research. All of it. Every scrap of paper that led to Twilight Sparkle thinking up the matrix she did. Burn every single one of her notes on the subject. Put memory charms on all the unicorns who were present during the test. Come up with a reason for everypony to avoid the test area. Never let another living being go back there.” The Harbinger's voice was completely serious. Celestia nodded silently as he spoke.

Silence reigned in the room as Celestia tried to process everything. “You can never tell her this, of course, but I do have to give Twilight Sparkle credit; she's the first being in the history of existence to think to use magic to achieve an atomic detonation. You've got one clever little unicorn there, Princess.” Had the situation been different, Celestia would have smiled proudly.

Instead, Celestia simply sat in silence. Hours passed. The Harbinger said nothing and eventually, mercifully, flipped the drawing over to hide the image from her view. It did not help. The Sun Princess could still see the image as clearly as if she was still staring at it. Celestia realized the image would likely stay with her forever.

Eventually, Celestia stood shakily and moved to the balcony beside him. Her sister's moon was bright. Canterlot proper was arrayed before them. Candles in windows pointed out the city's night owls as most ponies slept peacefully in their beds. Somewhere, Luna kept watch over Equestria from a silent perch.

The two immortal beings stood in silence for what seemed like an eternity. Celestia glanced over at The Harbinger whose gaze was locked firmly to the sky.

“Why do you do this?” The Harbinger slowly turned his head away from the sky and looked at his hands.

“You know why. You, your sister. A couple other beings in the universe. You know what its like. To be eternal. We live.......we love.” The last word was barely a whisper. “Then the ones we........grow attached to.....die. They die and we are left to mourn. And eventually we forget who they were, but we are left with the sadness. Cursed to cry over people and ponies we can't even remember.” His voice had lost the steely resolve of earlier. In fact, his tone was practically mournful.

The Harbinger looked down at Canterlot and smiled. It was a sad, sad smile. The kind of smile only one who has lost a thousand generations of friends, family, and lovers can wear. Truly, the sad smile of an Immortal.

“I thought that....maybe.....maybe if I could save a few of them.....maybe I could take some comfort there. I don't remember much of my world....God it was just so long ago. You truly have no idea how long I've been cursed to walk across these bastard skies.” His voice had an edge of bitterness to it as he pointed an accusing finger at the stars.

“But....one of the things I do remember is.....I had a love. I can't remember her name. I've tried, and tried, and tried. I suppose I'll never know what it was....but I remember that there was a day...we were together. We were having a picnic in a park or something. There was grass, and a blanket. And her eyes, god her eyes. I remember those clearly.....” Celestia looked away respectfully for a moment and pretended not to notice as the Harbinger wiped away a tear.

“We were sitting in this park, and it was sunny. The sun was beating down on my face, and as I was staring into her eyes, she said something. I........whatever it was she said, I suddenly felt this just.....perfect feeling. It was like, all the universe just sort of fell into place around us, and everything was clear. A moment of absolute, perfect serenity.

Then there was a flash, and then more.....then heat. Then nothing.” Celestia said nothing. She was struggling to contain her own tears. Few things were able to crack the motherly facade she often wore, but she could truly understand the immortal standing beside her on her balcony.

“That is why I do what I do. I figure if, maybe, I can just create one single moment like that....all this will have been worth it. And so, I travel. I've spent eternity searching for just one more moment like that one.”

Celestia was silent for several moments before deciding it was safe to speak again, and that her voice would not crack. “Then why come here? To this world? Why stop your search just to stop a possible catastrophe on an insignificant little planet?" The Harbinger nodded.

“Because, my dear Princess, in all the places I've traveled, in no place else have I ever thought that there was truly a chance for another moment like the one I search for to happen. Until I saw you and your sister. When your parents built this world from ash and fire, you two played here for a thousand years. Two immortal fillies, years passing like seconds. So care free. I watched you both from the time you were born. As a matter of fact, I helped deliver Luna.” Celestia was startled by this revelation. No pony alive even knew of the most ancient of times. Before she and Luna had allowed the ponies to control their own fates long enough to forget the two Sisters, only to return to restore peace to Equestria.

“Your Mother...oh how I miss her. You have her eyes, you know that?” The Harbinger sighed. “Yes, but you inherited your Father's temperament. At least Luna inherited your Mother's sense of humor.....you know, I still remember the time she hid the moon. Oh your Father was absolutely livid! In fact, he decided that if your Mother was going to hide the real moon, he'd just make another. You should have seen it. The absolute ugliest jumble of asteroids that you've ever seen! And talk about lumpy! When your Mother saw it in the sky, she flipped! Made him reorder the whole solar system...twice!” The Harbinger and Celestia both doubled over in laughter.

Eventually, the laughter faded and the two wiped the tears from her eyes. “But, as for why I'm here......I never expected that I'd get to experience Serenity again. But I figured, maybe, if I could just make it so that someone....or I guess somepony, could experience it at least once.........but those weapons I talked about. They'd end it all. Just like I showed you.” All the laughter was once again gone from the room, replaced by the returning atmosphere of sadness and dread. The Harbinger turned Celestia's head to look him in the eyes.

“Please, Tia. Please, help me make my eternity worth something.” Celestia blinked, and the Harbinger was gone. Without a second glance back towards the city below, Celestia slowly walked back into her quarters and closed the glass door behind her. With the utmost care, she picked up a blank parchment from her desk as well as a fresh quill.

My Dearest and Most Faithful Student Twilight

I would like for you to gather together your entire research team and proceed to Canterlot immediately. I would also like for you to bring any and all reference material used and all notes related to the project. Something has come up that requires all the material and researchers involved. Please make sure to bring everything.

And no, Dear Twilight, you are not in trouble as I have no doubt you are fearing. It is merely a necessary step considering the importance of this project. I will explain in further detail when you arrive. I will have dispatched a train to transport you straight to Canterlot by the time you read this.

Sincerely,

Princess Celestia

As the letter disappeared in a puff of green smoke, the notepad on her bed caught her attention. Hesitantly, she picked up the notepad and turned it around to face her. She gasped in shock.

In place of the horrific scene of death and destruction she had been expecting, there was a black and white sketch of four ponies. Four Alicorns, to be specific. One was a large white stallion with one wing placed protectively over a midnight blue mare who was curled up on a huge, bed sized cushion. The look on both of their faces was bliss as they looked down at two small bundles of cloth tucked against the mare.

Inside the two bundles were two Alicorn fillies, one white and one dark blue. Celestia smiled, not the motherly smile of a ruler or the sad smile of an Immortal. For one brief moment in time, Celestia wore the smile of a little filly, warm in the arms of her parents. In the bottom right corner was an exaggerated signature.