"…How is that possible…"
Saber stared at the scene before her in disbelief.
At the very moment Irisviel was about to be struck, a pitch-black aurora descended from the sky.
It was a boy whose presence could only be described as a shadow.
Clad entirely in Assassin attire, his face hidden behind a white skull mask.
He appeared before Irisviel and, with a casual swing of his aurora-like blade, cut down the otherworldly monster in a single strike.
A severed tentacle crawled along the ground, trying to climb up his leg.
He crushed it underfoot without hesitation.
"…Ah…"
Saber was too stunned to speak.
Black robes and a white mask. No matter how she looked at him, he should have been an Assassin.
But that was wrong.
He was not Assassin.
He could not be Assassin.
Because more than anyone, Saber understood the truth of the sword he wielded.
Even stained in black, there was no mistaking it.
It was the Holy Sword of the Lake, Excalibur, the blade that had accompanied her through countless battles.
And yet…
This holy sword, the symbol of Camelot's glory, now emitted the aurora of a tyrant, the fallen king who once ravaged Britain.
Saber's voice trembled.
"Wait… that sword of yours…"
Now that she was no longer viewing that black radiance as an enemy, it seemed impossibly beautiful.
Shirou did not look her way. He continued cutting down monsters as he spoke in a low voice.
"Don't lose focus."
"!!"
That single warning snapped Saber back to her senses. She tore off the tentacle wrapped around her neck and crushed it in her grip.
Caster, who had been reveling in ecstasy, flew into a rage the moment he saw the dark figure intrude.
"Who are you!? Have you come to interfere with me and Jeanne!?"
Although his arm had been severed by Shirou just moments ago, Caster showed no sign of recognizing him.
This was because Shirou had asked Lady Avalon to apply a cognitive interference spell to him. A strange distortion surrounded him, like an unfocused image, his outline always blurred and indistinct.
In a way, it resembled a certain Berserker's ability, "For Someone's Glory."
Of course, Shirou's main concern was avoiding detection by Tokiomi Tohsaka and the others. He had no intention of revealing himself this early.
He raised the black blade and pointed it at Caster, his voice calm and cold.
"There is no need to know who I am. I am but an insignificant shadow that has already passed on.
I stand here now only to pass judgment upon you, a wielder of twisted arts."
"What did you say…"
Caster's eyes widened, his already pale face turning even more bloodless.
"You mean… you are a messenger sent by God?"
Shirou blinked.
"Hm?"
"Impossible impossible impossible impossible impossible! An angel descending to the earth? God delivering judgment upon me? That cannot be true!"
Caster clawed at his hair, shaking violently as he screamed in hysteria.
"Jeanne's death already proved it. God's holiness is nothing but a lie. There is no salvation in this world. The prayers of the lamb will never reach the heavens, and human evil will never be judged!
God's authority, God's mercy, God's judgment, none of it has ever existed! Nowhere! It does not exist anywhere… it shouldn't!"
"… "
Shirou glanced at Irisviel beside him in silence. She gave a helpless shrug.
"I see."
Caster suddenly fell silent, his expression turning eerily calm, as if a switch had been flipped.
His eyes widened, teeth clenched as he spoke through gritted teeth.
"I understand now. Completely.
God is still trying to claim Jeanne's soul. That is why he sent you to interfere with me."
Shirou: Huh?
"Jeanne has only just been revived, and already you and your god have come haunting her again, trying to turn her once more into a puppet under your control!
Ahhh! How shameful! How tragic!
How utterly despicable! Don't you think so, Jeanne!?"
Faced with Caster's impassioned outburst, Saber's expression remained calm and unmoved.
"You abandoned your God and angels once before, and now you dare show yourselves again before her after her resurrection. What shamelessness!
Unforgivable! I, Gilles de Rais, will never allow you to defile her soul again!"
Shirou rolled his eyes.
So now he's getting all fired up. Who exactly is the villain here?
"Jeanne, please remain calm. I will… I will surely free your soul from God's curse!!!"
The grimoire in Caster's hands seemed to respond to his shout, pulsing with a sinister crimson glow as its pages flipped rapidly.
Hundreds of monsters burst from the ground. Their writhing tentacles filled the forest, surging toward Shirou and Irisviel behind him.
At that moment, a flash of golden light cut straight through the monstrous horde.
It was Saber.
With a restrained blast from her holy sword, she forcibly tore open a path and returned to her Master's side.
"Saber!"
"Are you alright, Irisviel?"
"Y-yes, I'm fine. Thanks to…"
Irisviel looked at the dark-clad boy in front of her, unsure how to address him.
"Um, excuse me…"
"Save it for later."
Shirou spoke flatly without turning around.
Irisviel froze for a moment, then quickly nodded.
"Ah, yes, understood.
Saber, can you still fight?"
Artoria glanced at the inverted holy sword in the boy's hand. A strange competitive spark flickered in her eyes as she nodded firmly.
She stepped forward and stood beside Shirou.
"Let me ask one thing. You are not the 'angel' he spoke of, are you?"
Shirou kept his gaze fixed on Caster, who stood at the rear of the monster horde, and replied without the slightest change in expression.
"And are you the 'Holy Maiden' that madman keeps talking about?"
"Of course not."
"Then that settles it."
Almost at the same time, both of them gripped their swords and took their stances.
"Unknown wielder of the demonic sword, thank you for saving my Master.
As you can see, Caster has no intention of letting you leave. Would you be willing to fight alongside me for now?"
Saber extended the invitation with unwavering composure.
Shirou's answer was simple.
"Don't slow me down, wielder of the holy sword."
Instead of getting angry, Saber smiled faintly.
In the next instant, a gust of wind swept through the forest.
Saber released Invisible Air, revealing the Holy Sword of the Lake resting within its magnificent scabbard.
Irisviel blinked in confusion.
"Saber? What are you doing?"
Without hesitation, Saber drew the sword and tossed the scabbard behind her.
"Irisviel, hold onto this for me."
"Huh… ah, okay!"
Saber gripped the radiant golden sword with both hands, a slight smile forming on her lips.
"Don't slow me down… I'll return those words to you.
Demonic sword wielder, if you cannot hold out, say so. I will make up for your share."
"Unnecessary concern. Just worry about yourself, wielder of the holy sword."
Trading barbs, Shirou and Saber charged forward together into the endless swarm of monsters.
"——————!"
Golden starlight and pitch-black aurora illuminated the forest in an instant.
...
"…So strong."
Irisviel stared in amazement at the two blood-soaked figures.
The holy sword and the demonic sword swept through wave after wave of otherworldly monsters with unstoppable force, mowing them down like grass.
Endless hordes of tentacled creatures surged forward, only to be cut down the instant they came close.
Having fought those monsters herself just moments ago, Irisviel knew very well that they were not foes whose only advantage was numbers.
They were brimming with vitality and Mana, built less like living creatures and more like weapons, their bodies covered in lethal fangs and suckers. They were monsters born to ravage humanity.
And yet before the wielder of the holy sword and the wielder of the demonic sword, those same monsters had become the ones being ravaged.
A few minutes later, the forest had already turned into a foul mire.
They fell in swaths like harvested wheat, and the layers of corpses, mountains of flesh, scattered entrails, and spilled bodily fluids merged into a chaotic scene more horrifying than hell itself.
The monsters' innards released a nauseating stench, giving rise to a toxic miasma. Any ordinary human without magical training would probably die from rotting lungs after inhaling even a single breath of it.
Thanks to projecting Excalibur Morgan and the magecraft of Lady Avalon, Shirou had received a tremendous boost in strength.
Even so, he still had not used his trump card, the Dead Count Shapeshifter Command Spell. In terms of raw physical ability, there was still a gap between Shirou and the Three Knight Classes that he could not bridge.
And yet, through swordsmanship and experience alone, Shirou displayed battlefield prowess that did not lose to Saber in the slightest.
Most astonishing of all was the coordination between the two.
This was clearly their first time fighting together. In fact, today was the first time they had even spoken to one another. Yet they moved like comrades who had fought side by side for years.
Every motion, every adjustment in position flowed naturally and flawlessly, as if it had all been rehearsed in advance.
To Irisviel, it looked like the latest Hollywood action film.
As for the two fighting at the center of it all, they felt that harmony even more keenly.
Beneath Shirou's skull mask.
Upon Saber's composed and beautiful face.
Both wore faint smiles that were almost impossible to notice, born from the sheer exhilaration of the battle.
In just over ten minutes, they had already slain more than five hundred monsters.
Even so, the number of tentacles showed no sign of decreasing.
Despite fighting through such a bloodbath, Artoria's beauty had not diminished in the slightest.
Shirou's expression could not be seen beneath the mask, but judging from his steady breathing, he was just as untroubled.
Saber leaped back one step and stood back to back with Shirou.
"Have you noticed, demonic sword wielder? It is the grimoire in Caster's hand.
As long as he still holds that book, the monsters will continue to multiply without end."
Shirou nodded and gave a quiet "Yeah."
While cutting down a monster lunging at Shirou's left, Saber curled her lips in a teasing smile.
"So you failed to notice after all, demonic sword wielder."
Shirou swung his sword and bisected the monster coming at Saber's right, immediately firing back.
"Looks like you're getting tired enough to start talking nonsense, holy sword wielder."
In truth, Shirou had already seen through it.
Rather, the moment he first saw Caster, he understood the principle behind it.
That human-skin grimoire of Caster's was essentially a magical reactor core.
Much like the Dead Count Command Spell on the back of Shirou's hand, it not only stored an enormous amount of Mana, it also had preloaded spells built into it.
Caster himself could not even use magecraft. He had always been relying on that book to cast spells.
Before this, he had opened an otherworldly passage in the forest through a living sacrifice ritual.
As long as the grimoire kept supplying the Mana needed to maintain the rift, it could go on summoning monsters forever.
That was the truth behind Caster's endless stream of tentacles.
"Now that we know the secret behind the monsters' endless growth, there is only one thing to do."
Saber turned her head slightly, speaking to Shirou in a tone tinged with challenge and anticipation.
"Since you are holding that sword, you should be able to do the same thing I can, correct?"
Her words were vague, but Shirou understood her meaning immediately.
"You clear the monsters in the way. I'll deliver the finishing blow to Caster."
Saber nodded.
"Mm, let's do that. Show me your aurora once more."
They did not even exchange a glance. Just by standing back to back, they understood each other perfectly.
"What are you two whispering about? Saying your prayers before you die?"
Caster stood about a hundred meters away, continuing to hurl mocking taunts at them.
At this point, what Shirou and Saber were fighting wasn't even him, but his Noble Phantasm, Prelati's Spellbook.
Caster himself remained like a spectator in a safe zone. As long as he kept a relaxed posture and occasionally threw in a few curses and jeers to provoke his enemies, his "attack" was already effective.
"Taste terror! Sink into the abyss of despair!
You'll be drowned by these monsters with neither honor nor glory, suffocated to death!
What a disgrace that must be for heroes!
Ah… let that beautiful face of yours twist in agony, Holy Maiden!"
"Unfortunately, I'm not a hero."
"Unfortunately, I'm not a Holy Maiden either."
Shirou and Saber stepped forward almost at the same time. But the one who moved first was the girl wielding the holy sword.
"Strike Air!!!"
A radiant golden light burst forth. The gale spiraling from the blade compressed the surrounding air, forming a Mana-charged shockwave that shot straight toward Caster a hundred meters away.
Between Saber and Caster stood a wall of flesh made of thousands of grotesque monsters. Yet before they could even react, they were blown apart by the slicing wind.
In an instant, hundreds of tentacles were shredded, and Strike Air showed no sign of slowing as it surged forward, aiming to crush Caster along with them.
But at that moment, the ground in front of Caster erupted as countless massive tentacles burst upward.
It was a defensive spell Gilles de Rais had prepared in advance. There was no way he would stand on the battlefield without protection.
Boom!
Even tentacles as thick as tree trunks couldn't stop Saber's wind strike.
Though they were blasted apart, they served as a temporary shield, buying time for their Master. Caster scrambled desperately, barely escaping the range of Strike Air.
But this, too, had been within Saber's Instinct.
From the very beginning, she hadn't expected to kill the seemingly insane yet cunning Caster so easily.
Breaking through his defensive magecraft was enough.
The rest she would leave to the one she trusted.
"Hah… hah… hah…"
Caster braced himself on his knees, panting as he rejoiced in having narrowly escaped. Just as he lifted his head, ready to resume his taunts, he saw the figure of a reaper standing before him.
"Hammer of the Vile King…"
The air surged. Mana roared.
Shirou raised the inverted holy sword high and calmly called out the name of Britannia's tyrant.
"Vortigern!!!"
A second impact followed Strike Air.
Though it was already night, an even deeper darkness appeared.
A black aurora that devoured all light.
Like the breath of an evil dragon ravaging the land, it tore through earth and forest alike, burning everything into scorched ruin.
"Aaaaahhhhhhh!!!"
Gilles de Rais screamed as he was swallowed by the light.
The dragon's breath tore through the forest, pierced the sky, and finally dissolved into the night.
When the dark radiance faded—
All the otherworldly monsters had melted into pools of blood. The tentacle army from moments ago seemed as if it had never existed.
In the silent forest, only Caster remained, most of his body burned away, along with Prelati's Spellbook lying on the ground.
"Ugh… it's not over yet… I haven't saved Jeanne…"
Perhaps because he had absorbed enough life force from the citizens of Fuyuki, Caster still hadn't died. Even with only his upper body remaining and his Spirit Core shattered, he continued to crawl forward.
He struggled toward the grimoire.
Just as his fingers were about to touch Prelati's Spellbook—
Shirou drove his sword down, pinning his hand to the ground, and calmly picked up the grotesque human-skin grimoire in his place.
…
…
No matter how detestable he had been in life, after Caster's death he turned into beautiful golden motes that scattered into the wind.
When a Servant returns to the Throne of Heroes, their Noble Phantasm should vanish along with them.
And yet, strangely enough, Prelati's Spellbook remained.
Shirou's curiosity was piqued, and he decided to take a closer look at the bizarre grimoire.
"Let's see… what language is this…? Not English. I can't understand a word…?"
"Hehe, it's Italian."
Shirou turned around to find Irisviel smiling behind him. As she leaned closer, her long hair almost brushed against his cheek.
"You can read Italian?"
"Mhm. Interested in the book? I can read it aloud for you."
The silver-haired homunculus placed her hands on Shirou's shoulders and began reading.
It seemed to be a record of strange creatures from ancient times. The text was obscure, and every line carried an unsettling, ominous tone.
"Irisviel."
Saber walked over, clearly displeased.
"Are you two seriously planning to stand here and start a book club?"
They had just gone through a life-and-death battle, and now they were calmly reading a book in the middle of a field of corpses and blood. It was absurd.
Seeing Saber's expression, Irisviel covered her lips with a smile.
"Oh my, Saber… are you jealous?"
"Wh…!"
Saber shot a glance at the dark-clad boy standing close to Irisviel and frowned.
"And why would I be jealous of you?"
Irisviel smiled brightly.
"Because you and Mr. Demonic Sword User were fighting so passionately. I was completely captivated watching from the side~"
She tilted her head slightly.
"Hm? Were you assuming I was jealous of you?"
"Irisviel!!"
Artoria snapped, her face flushing faintly despite her irritation.
At that moment, she felt someone staring at her.
"…"
Saber turned toward the boy who had just fought beside her.
"Is there something on my face?
Let me make this clear. It's not what Irisviel said. Please don't misunderstand."
She frowned slightly.
Was it just her imagination? The way he was looking at her felt… complicated.
"…"
Shirou stood frozen, unable to say a word.
"Mr. Demonic Sword User, aren't you going to keep reading?"
Irisviel asked as she took Prelati's Spellbook from his hands.
Shirou replied casually,
"Destroy it as soon as possible. It's extremely dangerous. Just like Caster, it shouldn't be left in this world."
Throughout the entire battle, Shirou had kept a cold, detached attitude.
From the moment he joined the fight to the moment Caster was defeated, even though their coordination had been flawless, he had never once looked at Saber's face.
Only now, after the battle, when Saber approached him on her own, did he finally get a clear look at her up close.
Her appearance matched exactly what he had seen before.
Flowing golden hair, soft and radiant.
A flawless, dignified beauty.
Cherry-blossom lips, eyes that had turned a clearer shade of green yet remained noble and striking, and a petite frame that carried a presence no less imposing than any man's.
Most importantly, the sword in her hand.
Excalibur.
Without a doubt, it was the Holy Sword of the Planet, forged from the life of the fairy of paradise.
Yes.
This was supposed to be a moving reunion across worlds.
And yet—
What?
Shirou's mouth fell open.
…She wasn't Morgan.
Even though Saber looked exactly like Morgan.
Even though she held the genuine Holy Sword of the Lake.
Shirou could not be mistaken. There was no way he could be.
No matter how similar they looked, no matter how close their presence felt, no matter how radiant and sacred that sword was—
She was not Morgan. Absolutely not.
"So…"
Staring blankly at Saber's face, Shirou asked,
"You're not actually King Arthur… are you?"