A/N: This was created as a thought experiment after I read some fanfics of other crossovers with Halo. So I decided it would be fun to try it out with Fate/stay night. Please note that it did not quite follow any route of Fate/stay night; however, it can be simplified to be the Fate route with elements of Unlimited Blade Works and Heaven's Feel.

I'll be speeding through their childhoods since it's not too relevant to the main story, but I promise I'll revisit it when I get the chance.

I do not own Fate or Halo; they belong to their respective owners.

At first, Artoria Pendragon could feel the shock of being ripped away from Avalon. She had been sitting in a sprawling wheat field that was acres upon acres. Artoria had been waiting for the love of her life, Shirou Emiya. She was waiting for him to finally find his way to Avalon and reunite the star-crossed lovers. She then began to panic. What if Shirou returned and she wasn't there to greet him? What would indeed happen then? She could not see where she was. For all she knew, she was in a pitch-black space with no visual clues as to where she was. Now that she began thinking about it, she also realized that her skin felt warm and wet. Am I submerged in some sort of liquid? Artoria thought to herself privately, and It's not that she could vocalize her thoughts anyways. After all, she was under the liquid's surface, with no access to oxygen to carry her voice. Wait a minute. Why wasn't she drowning? Indeed she would have gotten that reflex to attempt to swim up and gasp for air. Then, she felt that there was something where she felt her navel should have been. If Artoria could widen her eyes, she would have certainly.

Is this one of Merlin's cruel jokes? She was being born again. She was sure of it. And there was nothing she could do about it. It was one thing to be an infant experiencing something they would forget in a few years. She knew it was a different story to put an adult through such an experience. She could feel the contractions occurring around the womb of her mother. In the moments between her and her imminent birth, Artoria thought about what her new parents would be like and was silently praying that she would be meeting Shirou again. Perhaps she would also meet the others once again. It was a desperate hope, but that was all she could afford to go on at the moment, pure unadulterated hope. Perhaps the great divine would finally reunite Shirou and Artoria after that fateful battle with Gilgamesh and Kirei Kotomine. Which reminded her that if she ever saw Gilgamesh again, she would make sure he stayed dead this time. She didn't need her opportunity ruined by a man who did not know boundaries or the meaning of the word 'no.' It would take a while for Artoria to be born, or perhaps her frame of reference was thrown off by her stay in Avalon. She did not know. Back to contemplating about was happening in the outside world. Was she in the past, present, or future? It was a genuine question she wished to ask, especially if Merlin were involved with such an endeavor. Alas, she would not be surprised if that were the case. With very few leads inside the womb, Artoria tried to think to herself about the eccentric wizard, and maybe she still carried the connection to Avalon.

Merlin, where am I in the lord's name if you can hear me?

Artoria heard the voice of her accursed mentor, "Ah! Artoria, good to hear from you. I wasn't sure if you safely exited Avalon and if you were in one piece. We have a good start, then."

Artoria rolled her eyes, or at least she thought she did. You still haven't answered my question, Merlin. I have reincarnated. Where? Why?

Merlin's voice conveyed an almost bittersweet tone to it, but she could tell that he was doing his best to conceal such emotions: "You, my dear King, are being reborn in the year of our Lord two thousand five hundred and ten… As to why maybe the universe took pity upon you for once!"

She could understand Merlin's assurances, but it didn't help her. Her mind was zeroing in on the fact that she was more than five hundred years after she last graced the mortal realm. So much was bound to have changed. Her mind returned to Shirou once again, focused on her soulmate, albeit one who had lived over a thousand years after herself. Where is Shirou, then? Merlin quickly reassured her that her sheath was also being reborn. Words that finally brought some modicum of relaxation to her mind, Shirou was here! Somewhere in this galaxy, all she needed to do was find him. It was then that the final contraction occurred.

Alis was her new name. Alis Morgan. She wondered if this was another cruel joke arranged for her by the divine. Her having a surname that correlated with the given name of her sister was an unexpected development. Her sister ultimately contributed to her death at the hands of Mordred. Artoria still thought of herself as Artoria, but she had to admit that her new family was instead caring for her need. She was an only child within such a family, so there was no need to worry about a mysterious sister conspiring against her and trying to get her killed. Carter Morgan and Lisa Morgan were her parent's names. Life as a child was undoubtedly difficult, especially considering she was an adult before. Bodily functions would be out of her hands, ones that Artoria usually would do entirely autonomously. She privately wondered if her parents believed she was more intelligent than she looked. Artoria also began to scowl, thinking that she would survive the education system of the distant future. Hopefully, nurture was superior to nature, and Artoria doubted people had gotten inherently more intelligent than when she was alive in the sixth century.

She was five years old and could walk and do most things independently. Admittedly the food her parents made was better than most food she had known throughout her life, with the glaring exception being Shirou's food, which pleased her olfactory senses so much that she melted in place. Bringing her mind back to her sheath, it's almost as if she could feel something pulling at her.

Merlin. what in God's name is happening? It's not like I brought Excalibur and Shirou brought Avalon, right? Artoria thought to herself.

Merlin chuckled. It seemed the eccentric wizard had something else in mind. "Well, let's just say I pulled a few strings, but this will be the last I can directly interfere here before someone like Akasha notices." Artoria was puzzled by what he meant by this when suddenly the golden sword Excalibur materialized within her hand. She was honestly shocked that Excalibur had managed to return to her from the lake. She would eventually have to find and give Vivian her utmost gratitude. But that was a topic for discussion and reflection later. Artoria quickly turned around and began looking around to ascertain if anyone had witnessed the significant abnormality she had inadvertently caused. When it became apparent to her that no one else had seen the return of the legendary King Arthur, she began to connect again with the legendary sword. The sword promptly dematerialized within her hand, but she could feel the blade now residing in her body. That wasn't the only thing she could think at the moment; she began to experience sensory overload. The feeling she had been getting from the sheath was more potent than before. It was acting almost like a compass for her on this planet. It may not have been Earth, but Shirou also lived here. For her, that was enough for it to be home.

Alis quickly ran inside and began putting on her coat, with her mother noting that she was going off in a hurry. Before her mother could try to stop her, Artoria was already out of the door. Artoria ran down the street, under the limelight. Nothing would stop her from reuniting with her long-lost love. Artoria looked behind her shoulder, where she could see her mother quickly scrambling to chase after her. It did not matter. The warmth in her heart was getting warmer; it was a feeling that continued to drive her forward; she didn't know how far she was running. She was panting. Her little legs were on the verge of failing.

In the distance, Artoria's eyes spotted something. It was a short girl with ethereal blonde hair, a girl who had red eyes. It was something that Artoria could recognize anywhere in the world. No matter what world this was, it was Illyasviel von Einzbern. And she could see to her right was her beloved Shirou Emiya. Those golden eyes and red hair were indistinguishable, even if he was only five. Artoria was now close enough that the other two could see a blonde girl barreling toward them. She began to slow down and noticed her mother closing the distance and eventually catching up to her.

It seemed that her mother was distraught, understandably so. She didn't want to have her child unattended, and Artoria was glad she had such a caring mother, "ALIA MORGAN! DO YOU REAlIZE HOW WORRIED I WAS ABOUT YOU?! TELL ME WHEN YOU WANT TO GO OUTSIDE! IT WAS DANGEROUS!" Eventually, her mother calmed when she saw Illya and Shirou's parents and apologized, "My apologies, my child here managed to run off, and you know these little ones can be speed demons."

Shirou's parents nodded in understanding. Artoria also began eyeing Illyasviel and Shirou, who both seemed to have looks of recognition but weren't quite sure. She figured she would be on the safe side and introduce herself by her 'name.'

"Oh, hi, I'm Alis. What's your name?" Artoria courtesied. However, one could identify that her green eyes carried a sense of warmness.

Shirou also carried that sense of hesitant recognition before he decided to give her the name he had in this life; "Rikuto Ryuudou." Before he stepped aside and let his sister introduce herself to Artoria, "Asami Kornelia Ryuudou." Illya then asked to come with her to the nearby playground. "Say, Alis, do you want to head over there and play?" Giving her classic smile, not the murderous one, of course.

Artoria nodded, she looked up to the parents, and it seemed they were not against such a proposition. Her mother and Shirou's parents were hitting it off well. That was a relief. Maybe she wouldn't have to worry about in-laws in the next twenty years.

The three gathered around the swing set. There weren't other children around, so push now came to shove. Artoria's eyes met Shirou's, and she could only say one thing after years of waiting in Avalon, "Shirou? Is that you?" She had been waiting for this moment, thinking non-stop about reuniting with her lover. It was time, five hundred years after the Grail War. They were finally together again.

Shirou began to tear up and began to hug Artoria, "Yes, Saber, it's me. We're finally back together again. I don't want ever to let go, ever again." Time seemed to stop for Artoria; Shirou had not changed too much from the Shirou she knew and loved from the Grail War. It was sad that Rin and Sakura weren't here, as far as she could tell. She looked over to Illya, who seemed to have a mixture of bemusement and some other emotion she couldn't place.

Finally, Illya broke such a pregnant pause in the discussion and said, "Break it up, lovebirds, let's catch up on what happened since we were all separated. Onii-chan, why don't you explain to Saber-san what happened?"

Shirou separated from Artoria, and the three sat in a circle Artoria began to listen to how Shirou and Illya lived their lives after Artoria returned to her own time and eventually left for Avalon. Artoria was astonished and relieved that Shirou had not managed to go down the path of Archer EMIYA. Instead, he had managed to skirt away it barely and managed to follow his path in pursuing justice. Illya seemed to have eventually died from the limits imposed upon her body by being a homunculus. It didn't matter anymore. They were all here together.

She just wished that some of the others were here too. Irisviel, Sakura, Rin, even Kiritsugu. Alas, she only hoped they would all meet together in the afterlife.

Artoria began to think about magic and how different it felt. She knew she wasn't a servant anymore; she was mortal. Yet, she felt something different, like five hundred years had altered mana. She could tell that they still had magical circuits embedded in their bodies. If she squinted, she could tell that Merlin had indeed interfered with their births to give them the best chance possible; she saw that Illya somehow had the crest of the Emiya family.

Shirou got curious and fished something out of his pocket. Artoria's eyes widened; it seemed Shirou had managed to retain the reality marble that allowed him to utilize Unlimited Blade Works. Shirou had also discovered that he possessed Avalon. The Sword and Scabbard had united.

Reach Military Complex,

Epsilon Eridani System

August 10, 2517.

Halsey looked over the screen at all the candidates she managed to narrow her search. Optimally, she would have stayed with the original number of one hundred and fifty, but alas, she had to make do with only half of them. Halsey watched Déjà appear to her right.

"These are the seventy-five, Déjà," she said with finality. Alis Morgan, Rikuto Ryuudou, and Asami K. Ryuudou were among the many faces on the holographic screens. Déjà highlighted the three and noted to her operator that there was something off about them: "Doctor, as you know, these three carry irregularities throughout their bodies. Are you certain that these three should remain on your final list?"

Halsey sighed; the teams were all ready. Luckily they could save resources by getting three candidates from Alluvion. To her, that was equivalent to finding the metaphorical needle in the haystack and finding out all three were bundled up neatly. "Yes, Déjà, they are staying on the list; that is final." The Dumb AI nodded and flashed out of Halsey's office. The Ryuudou siblings and Morgan would be among the finest soldiers that humanity had ever seen. She had no intention to draw the ire of the Mage Association here, so she resolved not to examine what made them tick. Halsey looked to another screen, to one with whom she played the game with the coin on Eridanus II.

A/N: I'll let you folks decide this one for me. I thought magecraft had largely faded from the world by the time of Halo, especially considering that humanity has achieved FTL and flash cloning (which probably makes the homunculi almost obsolete). Or we can conveniently ignore it, which might cause future problems.