Disclaimer: Fate/Stay Night and League of Legends are the properties of Type-Moon and Riot Games respectively.

Chapter 0: Prologue

He was falling apart.

His every movement agony, his every thought a torment.

It seemed an impossibility for the bloodied tattered form to continue, for it even to be alive, but still it defied death, its many wounds bound shut by glittering scales.

Only its inhuman will kept the figure moving as it staggered towards the colossal abomination in the distance – the deformed Great Holy Grail bearing the reincarnating Angra Mainyu – which cast the cave in a hellish light and was surrounded by a sickly scarlet aura that curled ominously.

The silence was deafening, only the creaking noises of distant gargantuan mechanisms and a constant ringing filled its head.

'What was I supposed to do?' Flickers of thought rasped through a desolate wasteland filled with innumerable swords as harsh scraping noises echoed the figure's movements.

The shadows before it suddenly boiled and a jolt of adrenaline surged through its veins as the cogs of his mind sped up. His gaze was greeted by flailing tendrils of shadow surrounding a pair of embracing sisters; one of them limp and lifeless, held strangely tender in the arms of the other whose face was a rictus of distress.

'Ah, I remember.'

Gathering up the fragmenting pieces of his mind, Shirou sped towards the pair, almost absently dodging the shadowy tentacles which continued to thrash about, mimicking the anguish of their creator.

A few tendrils stabbed into him, but he shrugged off the shallow injuries – his body was made of swords after all. He had intended to use everything he had to destroy the Greater Grail, but there was something more important for him to use the last of his Prana on.

"Trace On."

The image of a jagged iridescent dagger coalesced in his mind and just as he neared the sobbing shape of Sakura cradling her fallen sister, the Anti-Thaumaturgy Noble Phantasm, Rule Breaker formed in his hand.

Jumping over a low-swinging shadow, Shirou rolled to a stop and in a smooth motion, lightly pricked the almost catatonic white-haired girl, dispelling her link with the unborn Servant currently attempting to incarnate itself. Sakura immediately fell limp and Shirou only had a few desperate moments to grab the falling sisters and lay them gently to the ground. Even as he did so, he distantly felt something latch onto him, but he quickly dismissed it as part of his imagination.

Around them, the shadowy maelstrom slowed and ceased, and in the unnatural calm after, the battered but still alluring form of a purple-haired woman appeared before Shirou. The pair was silent as they quickly scanned the two unconscious girls and it was with a slight lightening of his heart that Shirou concluded that both would live; Sakura was relatively unharmed and Rin's Magic Crest had already stopped her bleeding.

"Rider, can you bring them to safety? I'll finish this." Shirou's voice was hoarse, almost metallic and he had to strain to get the words out.

The Servant of the Mount's eyes were once again covered, yet Shirou could feel her gaze search his before she nodded once and gathered the unconscious sisters into her arms.

It was with a grateful smile that Shirou turned back to the black pillar topped with the twisted embryo, his thoughts surprisingly coherent as he considered his choice of actions, before unexpectedly the silence was broken once more.

"Come back to us."

Shirou almost didn't recognize the voice without its usual sultry tone, and when he turned to reply, Rider was already sprinting away as quickly as she could without harming her charges.

His spirits slightly buoyed, but the rush of adrenaline already dissipating, his body began to weigh even heavier on him and the aches and pains were returning with a vengeance. Just as he was about to turn back, something sparkling in the earth caught his eye. Kneeling down with some effort beside the dust-covered object, he picked up the object and hefted its surprising weight in his hand.

The Jeweled Sword of Zelretch, the Mystic Code he had Traced for Rin in her confrontation of Sakura. A single large oblong crystal knapped roughly into the blade for a short sword created by the feared Wizard Marshal Zelretch. Its inner workings were beyond Shirou's understanding, but from what Rin had managed to pummel into his head, it was capable of firing off a stream of destructive light by harnessing Prana channeled through the Kaleidoscope– what it did in essence was create a tiny opening to the same area for an infinite number of parallel worlds then draw in all of the place's Prana in order to power the Mystic Code.

'Rin must have dropped this after her fight with Sakura,' Shirou's thoughts wandered, his mind once again disintegrating in the absence of those most precious to him. Only Rider's echoing words provided him focus, their implications weighing heavily enough on him for him to recall his purpose.

He had intended to Trace Excalibur, the strongest Noble Phantasm he knew, or at least his bastardised copy of it in order to destroy the tainted Grail, but somehow he knew that doing so would destroy him, and he couldn't allow that to happen, not now.

For some reason, he was finding it easier to access the thought-processes and memories of EMIYA, as if something was gluing the fraying pieces of his mind and soul together, but it must have been just his delirium.

'After all, if my sense of self is fragmenting, it's not surprising if my mind can't recognize which of this jumble is mine or his," mused Shirou rather morbidly as he moved deliberately towards the repulsive birthing of Angra Mainyu, concentrating on how to deal with the abomination as he struggled with his more-than-half-dead body.

It was with something akin to surprise when Shirou's fragmented mind latched onto a promising idea, one that actually held the prospect of his survival.

And this was when the equally abused form of Kirei Kotomine loomed before him, looking near death, with a stain the colour of pitch where his heart would be.

The Church Executor hadn't even been trying to sneak up on Shirou, the red-head's single-mindedness gifting the other distorted individual the opportunity for first-strike.

It was a horrid parody of his former power as Kirei lunged forwards with an elbow strike, intending to finish Shirou before his strength failed him. At the last moment, Shirou caught a glimpse of the bloodied form in the corner of one silver-hued eye and fell back gracelessly, barely dodging the still-lethal attack.

Kirei quickly pivoted on one foot, lashing out in a blurring backhand which Shirou blocked thoughtlessly with the Jeweled Sword, but the force brought to bear still knocked his defence asunder. The Executor didn't even flinch as his hand was flayed open and its bones shattered, instead capitalizing on the opening created as some of his blood got in Shirou's eyes, continuing his spinning motion and sending a roundhouse kick towards his opponent's abdomen.

In an almost prescient move, Shirou inched his torso back but wasn't fast enough to avoid a glancing blow by the heavy boot, which was still enough to send the teen careening away.

Shirou spun to bleed off most of the kick's force, but the slight wobble as he got to his feet belied its damage.

The teen carefully observed the taller man as he concentrated on his defence, his opponent had the edge on both experience and physical capability, so he would have to be careful when engaging the other in close combat. Judging from the priest's near-death state, Shirou's best hope was to outlast his foe.

The two opposites stared unblinkingly at each other, when suddenly the false priest started to laugh hollowly to himself, his maimed hand covering his face, before directing a surprisingly amiable expression at Shirou.

"Ask it. The question that's been gnawing at you."

Shirou blinked. This hadn't been what he had been expecting. For a second, his mind was blank, refusing to shift away from battle-readiness. Was this a ploy? Any delay in their fight would only benefit Shirou as time grew scarce for the corrupt priest, so what then was the point in this? Best to humor the priest, and harsh as it may sound, cut down on the seconds of life left to him.

There was no point in asking how he was still alive, the apparition before him had no heartbeat and his life was already ebbing away. What then could Kirei be alluding to…? Suddenly, in a moment of clarity, Shirou knew exactly what the priest was waiting for.

"Why are you doing this?"

Kirei seemed almost proud, like a teacher who had gotten a satisfactory answer from a dim student, "Why? I'm a believer in that everything has the right to live. Why do you condemn it as evil before it's even been born?"

Shirou was shocked by Kirei's response, he had intended to strike during the priest's reply, but found that he was inexplicably bound to respond, "Don't give me that crap, it's already caused the death of so many. I can't let it be released."

"Is it evil just because it has killed? Even if his nature is evil, didn't everyone wish for him to be that way?"

The red-haired teen was dumbfounded; Kotomine's viewpoint was just too jarring.

"Humans don't have an absolute concept of good and evil. They become good or evil through learning, starting at zero and their decisions decide which is which. Now if humans are a coexistence between good and evil, such that even villains can have rare moments of good will and saints can behave with ill intentions. Then how about a being born evil?"

Once again, the priest's thinking was almost incomprehensible to Shirou, "So you think it's fine for him to be born even if he's someone who can only kill?"

"I believe that you cannot lay blame on what has yet to be born. Until its birth, there is no reason for any punishment."

"So you're saying that even if a baby is evil, it has committed no crime in being born."

"Correct." There was an eerie light in Kirei's eyes as he continued, "Since life begets both good and evil, nothing should be punished before it is born."

'So it is for this reason alone that he will pardon 'All the World's Evil'.'

Their continued banter was surprisingly cordial, juxtaposing with the increasingly hellish atmosphere surrounding them.

Kirei continued, "Even if Angra Mainyu's actions are evil, we still don't know how he feels about them."

"Eh? How he feels about his own actions?" Shirou didn't know why he was continuing this conversation, but he was compelled to finish it. Whatever it was.

"If he views his own actions as evil, and agonizes over them, then he's evil. But if he has no doubt in his existence and actions, then he's good. After all, if he functions as everyone wished, then he cannot be evil."

Shirou shook his head vigorously, "No! Just because humans are a mix of good and evil doesn't condone his existence."

Kirei smirked, "Didn't I mention before that there is no crime in being born? You can't condemn him for future actions. I want to know how it feels about its own actions. If it would be able to forgive itself for destroying and losing everything. Maybe then I'll discover the worth of life and my own existence."

Something about the other's spiel struck a chord within Shirou as he slowly realized why his opponent's presence always felt wrong to him.

"I want to know if it is fine to live as you are, when you're different from others. After all, just as you are a being which feels supreme bliss in others' happiness, I am one that feels the same in others' unhappiness."

Kirei's smile widened as comprehension dawned on Shirou, "Yes, we're the same. We both believe ourselves to be sinners, looking eternally for salvation that never comes, though it seems like our inclinations run opposite."

And with that, Shirou understood why Kirei had wished for this talk despite the disadvantageous nature of such an action, especially where time was so crucial. The meeting of two individuals so alike and yet so unlike presented a unique opportunity to someone who had never held anyone's understanding his whole life. Here was the prospect of understanding, of something almost akin to acceptance to someone starved for such, and the sharing of the motivations and the culmination of his life's goals was impossible to dismiss. Even if the very act itself threatened to unhinge all his plans.

The two individuals' gaze met, and Kirei's lips quirked into something that only a generous person might call a smile. For the first time in his life, the false priest experienced the emotion that he equated to be the closest thing he felt to happiness without the misfortune of others.

"It seems like this has been a waste of breath, there was never a chance for either of us to back down was there?" Shirou exhaled, a part of him satisfied, as he prepared himself for the battle ahead.

"I don't mind, it was interesting even if neither of us has much time left."

Both were beyond their last dregs and each now sought to snuff out the other's flame before their own extinguished. In the end, there had never been the possibility of either abandoning their way of life.

Kirei had to kill Shirou for his wish to come true, Shirou needed to kill Kirei before he could destroy the shadow.

With simultaneously howls, the two empty human beings rushed one another in a flurry of blows that their battered bodies should not have been capable of. Their final clash was purely physical; Kirei had nothing else left to give and Shirou couldn't spare any Od for his plan to destroy the Blacked Grailto work.

Both were inhumanly fast, their exchanges faster than the eye could follow. Kirei should have been faster and stronger, not to mention more skilled, yet somehow Shirou managed to keep up with the Church Executor.

It wasn't obvious given that neither opponent showed any weakness, but gradually the likely victor was becoming clear. Where Kirei was simply flesh and blood, Shirou's unique soul was exhibiting its effects further. Any injury inflicted on the teen seemed to heal itself over and become resistant to further damage, and if one could examine them closely, rather than truly being healed, the wounds were instead getting sealed by countless minuscule interlocking blades.

"What a troublesome body to attack," Kotomine's fists were but a mess of pulped flesh and jagged bone, his earlier injuries buried under their gory ruin, yet he continued to smash them unflinchingly into his opponent's weak spots. Shirou seemed to have forgotten the Gem Sword in his hand, using only hand-to-hand combat to devastating effect combined with his body made of swords.

But the thing was; Kirei's attacks didn't just target the surface, but the inner workings of the human body as well. Though the effects of Shirou's Reality Marble on his surface cuts assisted him, its attempts at repairing his internal injuries were doing as much harm as good.

Their fight wore on, more blades protruding from Shirou's flesh like so many daggers, leaving only his face unmarred. Kirei quickly took notice of this and started to aim more strikes at his foe's head, but where Shirou was willing to absorb blows to his body, he desperately protected his head, going so far as to sacrifice his arms to block the bone-shattering attacks. Only the countless blades shoring up his broken bones allowed Shirou to fight on.

Both of them were slowing; Kirei from the accumulation of his injuries and Shirou from the continuing materialization of his distorted soul. With an unexpected burst of strength, Kotomine leapt up, kneeing Shirou in the solar plexus and sending him flying backwards despite himself.

His breath knocked out of him, every subsequent breath came with a screech of metal on metal, and the effort of getting to his feet was accompanied by the squeal of grinding blades. Looking up to see Kirei charging at him with one of his mutilated fists cocked, Shirou sucked in great gulps of air to prepare for their continuing death duel.

The end came abruptly.

It was almost as if someone nudged his arm and just as their clash would resume, before either man realized, the glittering sword was protruding from Kirei's back.

Both Shirou and Kirei looked almost uncomprehending at the crystalline blade impaling the priest's chest, centered right on the ink-black stain. Their eyes tracked the sword to the grip of Shirou's hand, before their gazes met. Kirei looked confused for a moment, his eyes searching, yet his expression quickly morphed into what seemed to be amused understanding.

With surprising strength, Kirei declared, "You win, Shirou Emiya. You are the victor of the Fifth Holy Grail War and the last Master. Go and fulfill your wish at the Holy Grail."

Then he just crumbled away.

Shirou was left with his arm outstretched, the ritual sword in his hand stained black with ichor, his mind in turmoil. Kirei's last moments were unsettling – the last look from him had been oddly triumphant – but he had no choice but to ignore his misgivings, it wasn't like the priest knew his plans.

He wasn't far from the birthing Angra Mainyu now, but every step felt like an eternity. The fight with Kotomine had rendered most of his limbs almost fused into immobility, and it was only with the redhead's inhuman will that he was able to move.

Finally he was before the shadowy giant.

What little Od he had left surged through his circuits, but they felt different somehow. It didn't matter. He raised the Jeweled Sword of Zelretch in his hand. Though Mystic Codes – magic artifacts which enabled certain feats of Magecraft – should only work for those within a Magus' lineage, Shirou had never allowed convention, or petty mystic rules, to limit him. After all, he'd used Noble Phantasms, the crystalized mysteries of Heroic Spirits, and Mystic Codes paled in comparison.

The crystal sword began to glimmer with inner light as Shirou held it upright over his head, unknowingly mimicking his fallen protector. Shirou's circuits heated up as more Prana than he expected ran through them, and his body warmed as its prana channels flowed with life force.

With a wordless yell, he swung the Gem Sword as it suddenly blazed with light, then a blinding surge of prismatic light surged forth from its core, bisecting the dark pillar in an explosion of extraordinary power.

For a few seconds, nothing could be seen as Shirou sheltered his eyes while being battered by the back blast. But slowly, as the dust cleared, Shirou's stomach dropped as the bleeding pregnant form of the Greater Grail was revealed.

An immense gash in its side dripped sickening sludge and the unborn Avenger appeared to be writhing in pain, but its bulk was undiminished. Without warning, an incoherent scream resounded through the cavern, inhumanly loud and not even recognizable as human.

There was a sudden lull, and Shirou lowered his hands from his ears as he prepared to strike the Grail again. As his weapon glowed with light once more, a torrent of shadowy flames poured forth from the grotesque monument, and in a blink of an eye, the entire cavern was awash in darkness.

Only the area around Shirou remained illuminated and clear of the dark flames, and just as he was about to unleash another attack on the immense artifact, the gate of the Greater Holy Grail changed, and the swirl of eternity stared back at him.

For a timeless instant, Shirou didn't understand the implications as he stared into the gate through a veil of scarlet, blood dripping down his nostrils and leaking from his ears, then the light from the Gem Sword flickered and the gate was just a gate again.

'No.'

Scenes of an unholy blaze flashed through his mind and the sound of tortured monolithic factories echoed within his soul.

'They're safe.'

People around him dying.

'This can't be happening… Not again.'

All the blood vessels in his eyes had burst, rendering them an ominous crimson and bloody tears dripped unseen down the teen's expressionless face, falling onto the myriad of blades protruding from his flesh. The light from the crystal sword sputtered and vanished, yet the flames came no closer.

Shirou was assaulted by scenes of a Fuyuki City completely engulfed in unnatural flames, a disaster even worse than the one that birthed him. These fires were murky, even painful to look at. Everywhere people were just laying down to die; agony transposed by serenity.

His mind was cracking once more.

He desperately tried to shut out the images, but something kept shoving them into his brain, refusing to let up on his torture.

Then just when Shirou thought he would break, shatter like brittle glass, that thing showed him its crowning achievement, its trump card.

This would be the last straw, the one that broke the camel's back. But it just went to show that it didn't understand Shirou Emiya, not at all.

It showed him its first victims; a trio of women, one hunched over the other two protectively just as they were engulfed in an inferno. Shirou let out an uncharacteristic gasp, then gritted his teeth when the protective long-haired beauty faded away, unable to withstand the fiery onslaught. Then went completely silent as almost in slow motion, the pair of unconscious girls were consumed by the firestorm.

The entity waited, barely concealing its glee. Its triumph, its birth was at hand, and there was nothing left to stop it.

Shirou Emiya opened his blood-filled eyes as they gleamed with an almost otherworldly light, and even through the pall of crimson, they shone; one a pale silver and the other glowing gold.

"You Bastard!"

A yell of unadulterated rage punctuated by a fierce arc of light that impacted on the monstrous cradle.

Liquid metal flowed through his veins, a searing pain that focused his splintering mind as Shirou concentrated all of his wrath on its destruction.

They had been his family.

He had forsaken his ideals for them.

People he held even above the world.

And this thing had taken them from him.

Now he would make sure that the warped Servant would never see the light of day.

It didn't matter now if he died, all that mattered was that he took Avenger down with him.

The surrounding shadows fled from the deluge of light, unable to withstand the fury of the teen as he channeled the energy of infinite worlds through the Gem Sword at the Greater Grail.

But Angra Mainyu refused to perish as he responded with a viscous stream of muddy darkness, and the cavern rumbled with the impact between shadow and light.

They were at a standstill.

With his concentration split between defence and birth, 'All the World's Evil' was unable to overpower the crystal Mystic Code, but Shirou was at a deadlock too, his muscles turning to swords and unable to Trace anything since all his Magic Circuits were being used.

Shirou's vision was corroding. His whole body was transmuting into blades as he exerted himself beyond his limits.

'Angra Mainyu is winning.'

'No!'

'This is as far as you can go.'

'Never!'

"Shirou."

He blinked.

Had he imagined that?

A diminutive figure clad in grandiose robes walked into his vision.

'Illya?'

"Don't worry, I'll close the gate," the snowy-haired girl smiled, unaffected by the horrific vision that was Shirou.

It was an almost insurmountable effort to speak, "…Y-you won't be able to return if you do."

"It's the only way; after all, I want you to live."

Shirou tried to shake his head and for a moment his lance of light wavered and the column of shadows crept closer.

"Shirou… They would want you to live as well. So live on, for us."

The glittering scales of his neck ground together as Shirou vigorously shook his head and somehow the beam of ether pouring from the crystal sword actually intensified, "Illya…"

She cut him off, "You know, I'm glad we were siblings even if we aren't related by blood." She hunched a bit as if telling a secret, "Now let me show you a miracle. It's an application of sorcery that everybody would beg to see."

Her smile was radiant.

"No! You idiot, I don't want to see it. Don't go!" The words grated forth from Shirou's throat and real tears mingled with the crimson rivulets on his face.

Illya moved right up to the gate of the Greater Grail, "You said before that it's the duty of the older brother to protect his younger sibling right? This time, I'm the older sister… so I'll protect my younger brother."

'No… I can't let you sacrifice yourself for me…' Shirou struggled to say, but the words refused to budge from a throat which didn't even resemble anything human anymore.

"Goodbye Shirou, live a happy life."

And with a final smile goodbye, the gate closed behind her.

-oOo-

The tower crumbled, pierced by light.

A city remained silent.

A priest's wish was left unfulfilled.

A body of swords was left hollow.

A soul(?) was revived then sent on a journey.

-oOo-

In another far different world, a formless something emerged from a tiny rip in space.

The air was rich with Mana, beyond anything a magus could dream of, yet the soul, revitalized through an imperfect Third Sorcery needed an anchor. The Heaven's Feel had been incomplete, it had repaired the soul's cohesion but it still required a container lest it disperse.

In one instant to the next, a hazy silhouette appeared, superimposed over the soul, which gradually infused itself into the shape.

The fusion crept along; the outline steadily growing more distinct, its features becoming clearer as it slowly became recognizable as human.

-oOo-

AN: This is the first fanfic I've submitted online and has in fact been languishing in my hard-drive for several months while I considered what exactly to do with it. This was originally part of a larger chapter, but I've split it since I'm not satisfied with the second portion, and it made more sense to separate the prologue from the first chapter. Anyway, I wrote this mainly because the idea of combining the Nasuverse and Runeterra wouldn't get out of my head. The prospect of introducing Shirou to the conflict-filled world of League of Legends just screamed epic to me, and the storylines and backstories of the various characters seemed to yearn for Shirou's meddling.

Anyway, I'm not sure how often I'd update this. The following chapter shouldn't take too long (Primarily because most of it has already been completed), though it really depends on my motivation and free time.

Please read and review (fanfic authors live off reviews after all), comments, suggestions and constructive criticism are welcome, though flames will be ignored.