Well, before starting, I am going to clarify two things to avoid questions or the same things that I have already seen.

1- Why do I only upload Naruto stuff?

for the mere reason that I like the characters but more personally I feel that it is easy to handle and mold into what one wants, whether it is good or crap, that depends on each person how they do it, I can say that I am of the amount doing a naruto op but i'm okay mother you are free to criticize me if you want and i am free to do what i want with my things

2- the way of writing

I am not an expert like many who are here or who have already seen clearly that you will see errors like in the way I do the dialogues because I am not an expert so if it is the same thing you are free to say it I respect your opinion but Since I can respect it, I am free to ignore it, so reserve any insult without reason for yourself. Criticism that is intended to improve is welcome because, as I said, I am not an expert in doing these things and if I do it, it is merely out of fairness.

Now with those two things clarified, you are free to start reading or leave as you like.

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The Fourth Holy Grail War had begun a few weeks ago when all the Servants had been summoned, but with an anomaly that needed to be resolved by the overseer of the war, Risei Kotomine. For someone who rarely felt anything, it was interesting to see how this new anomaly in the war could change things. So, from afar, he let things take their course to see how they unfolded.

For the Fourth War, it was decided to create a humanoid vessel for the Holy Grail, one with both consciousness and independence, so she could defend herself from danger. The archetype was used as the basis to create Irisviel, who would be known as the latest model of Justeaze. Irisviel would become the mother of the ultimate homunculus among all those created in the past by the Einzberns, being the only one to have experienced motherhood and given birth to a successor.

Irisviel von Einzbern was tasked with the invocation to summon Saber to the war alongside her husband in a church, using as a catalyst the sheath of the legendary sword Excalibur wielded by King Arthur. During the invocation, everything had proceeded normally without any complications that could have hindered them, fulfilling its purpose by summoning the legendary King Arthur, who appeared as a young woman in her adolescence, slender in build with smooth, fair skin. She had fine-textured golden hair that seemed "to have been sprinkled with gold dust," and her face showed signs of both naivety and elegance.

For Kiritsugu, the Magus Killer, it could have been one of the best moments if not for one factor he hadn't considered when he was called upon by the Einzbern family to help them win the war. That little factor that escaped him came in the form of Naruto von Einzbern, a relative of Irisviel von Einzbern, who had no problem with this relative getting involved in the Holy Grail War; even his own family supported him by providing resources when he asked for them.

The seventeen-year-old brat was the Einzberns' rough gem, a prodigious magus since birth with a high level of understanding of magic. He was pampered to the point that the current head of the Einzberns took him as his apprentice, making him the future patriarch of the Einzberns when his time came. Some family members opposed this decision, but they kept quiet when the boy, besides having an intellect superior to that of the Einzberns, had developed two types of magic that his family had never shown before.

The first was developed in his eyes, allowing him to see magic from magi at an extremely clear level, also allowing him to see everything as if it were high-resolution thermal graphics and even see buildings through magical energy remnants and the flow of magical energy from entities around him. Furthermore, it allowed the user, when activating their technique, to nullify the loss of cursed energy, making them superior users in terms of durability. It also allowed the user to see beyond what normal people usually see.

The second type of magic led the boy to be in the public eye of any recognized magus from the three families in Japan: "Unlimited." This magic had a series of forms and based on it leveled up, allowing precise manipulation of space at an atomic level, giving multiple results and subsequent techniques within the general capacity. With space manipulation as the basic level of the technique, it had three standard forms and a "non-standard" one that went beyond unlimited. The technique itself operated in the same way as convergent and divergent sequences in mathematics. No matter how many times a number is divided, it will never be reduced to zero. Similarly, the technique prevents someone from getting close to the user no matter how close they are.

A damn monster at his young age, if you were to ask him himself, he might feel relieved that this potential monster was on his side, but that wasn't the case nor would it be because the brat was egotistical, narcissistic, and didn't obey anyone he didn't like or who was stronger than him. In this case, it was clear that the brat didn't like him at all and wasn't as strong as him, but he surpassed him in experience, though that didn't mean that if he wasn't careful in his plans, he could kill him without hesitation. He had seen him do it without hesitation when a stray magus tried to attack them on the way to the church where Saber's invocation took place. The only advantage he could see from his company was that Naruto and Irisviel had a deep connection, making anyone who wanted to harm Irisviel end up murdered by Satoru.

"I ask you... Are you my master?"

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The summoning of Saber had been carried out correctly without any other inconvenience during the night, allowing everyone to withdraw peacefully to the castle provided by the Einzbern family, staying there until the other Servants' masters made the first move.

Watching from the castle's rooftop was Naruto, watching as Kiritsugu played with his niece in the snow. If you were to ask him what he thought about the man, he would say that he was just one among many, only there to belittle him, but he explicitly knew that his comment would be a mistake because the man was not called the Magus Killer for nothing; he had plenty of merits to have that nickname. But he was just a man with vast experience in battle with firearms because he saw the deficiency of magic.

That was something he also saw even before the head of the Einzberns took him as his successor. Magi today were stagnant in a single thought, going for the root to know all the knowledge it could provide, something tempting if he thought like any magus, but that was not his case. He was an exception among thousands from his birth among the Einzberns, standing out for not adhering to the rules, working in alchemy as others would.

Although that was a topic for another time, changing his view to his feet, he could see through the roof inside the castle were two presences. One of them was his dear aunt Irisviel, the main reason why he was in Japan instead of Germany with the other Einzberns. Since he was young, he had wanted her to be his partner, but fate got ahead of him when he met Kiritsugu, even having a daughter, but that man was cursed to die in this war or in a few more years. He could clearly see with his eyes that behind that man was a curse that was killing him little by little.

But little or nothing would he do to save him; he had taken away the woman he loved, so death was what awaited him. They could call him deranged or sick for wanting to be with a family member, but that wasn't so strange among the Einzberns. Many had married among relatives to keep the blood pure, adding to the fact that in terms of humanity, his family was more homunculi than anything else. Both his aunt and her daughter were homunculi, so they didn't fit into the term humanity, so he had a free pass when she passed away.

As for the other presence he could see, the Saber-class servant summoned by the family to win the Holy Grail War, the intention was to summon the King Arthur of Britain, but who would have thought that such a legend would be a woman, and a strong one at that, who could be seduced by his charms because who could resist him, who since his birth had an appearance that was irresistible to the female opinion.

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"What are you looking at, Saber?"

"Your daughter and Kiritsugu are playing outside."

"Surprised?"

"I had the impression that my master was a more insensitive person."

"Well, I can understand why you think that."

"But if this is Kiritsugu's true face... why does it always change when he sees the white-haired guy?"

"Hmn... You mean my nephew Naruto?"

"Naruto? So that was his name, I see..."

"Well, it is true that Kiritsugu can act like a good father with our daughter, but with Satoru, it's different. Let's just say that they don't have the best history."

"I see, so there's a story behind the two of them."

Hearing that comment from Saber, he couldn't help but let out a slight laugh at what she said because it was true that there was a story behind them, but if he were to think about the short time that Kiritsugu and Naruto interacted together, he could talk about several things where they both started arguing more because Kiritsugu was a calm man until Naruto touched his sensitive points to argue with him when he was bored.

"Irisviel! This is not funny!"

"I'm sorry... but if you knew the short story behind those two, trust me, there would be one or two laughs."

Before that conversation could continue between them, a sound alerted Saber, who got into position ready to attack. She concentrated to know where her opponent was until she felt a presence behind her, turning quickly she was ready to attack with Excalibur's invisible scabbard to whoever was behind her. In a quick turn, she applied force to finish off her enemy quickly.

The attack was too fast for normal human eyes until the attack stopped abruptly in mid-air in front of Saber's emerald green eyes, which met with crystal blue eyes partially covered by sunglasses.

"Nice welcome, I like it, but next time, don't be so aggressive."

The new individual in the castle showed that it was Satoru using sunglasses that covered his eyes, only leaving them visible a little. He wore a long-sleeved black shirt and matching black pants.

"At what moment..." Saber said as she kept wielding her weapon and without lowering her guard.

"Hello Iris-chan, were you watching me?" Naruto mentioned with a playful expression as he took her by the waist.

"You know that I already have Kiritsugu in my life," Irisvel said as a smile formed on her beautiful face.

"You know that never stopped me, Iris-chan," Naruto said as he let go of Irisvel and looked at Saber.

"Besides, who would have thought that the ancient king would be a beautiful maiden?" Naruto said as he approached Saber, but she pushed him away, holding her sword in position.

"You're not allowed to get any closer," Saber said monotonously with Excalibur in her hands.

"Come on, Saber-chan, don't you want to know what it feels like to touch the sky?" Naruto said with a seductive voice as his glasses slid down a bit, revealing his beautiful blue eyes.

"My only purpose in this war is to reach its end," Saber said with a poker face.

"How cold... I like you like that," Naruto kept tugging at the loose rope where Saber was standing, causing her to twitch her eyebrow.

"Naruto... Shouldn't you be doing something else?" Irisvel said calmly as she kept looking at Kiritsugu.

"If you mean about the war, nothing really worries me; they're all too weak," Naruto said nonchalantly as he looked at his cellphone, something that neither Saber nor Irisvel noticed until the music from an otome game started playing.

"Are you mocking the weak?" Saber said with some confusion; this guy reminded her of someone, but she still didn't know exactly who.

"Only an idiot would mock the strongest," Naruto replied to Saber's question while still playing his otome game.

"Naruto... I need you to do me a favor," Irisvel said as she looked at the sky.

"Does Iris-chan want another child?" Naruto asked as he approached Irisvel.

"I need you to go investigate again; I have a feeling that this war won't go like the others," Irisvel said, becoming serious, which made Naruto serious too.

Without saying a word, Naruto disappeared from the place, reappearing far from there, looking down he noticed a small white-haired girl, obviously knowing who she was but not because of that, he would listen to her, however, he surrendered to her beauty inherited from her mother.

"Uncle Naruto," Little Illya said happily as she ran towards the white-haired blue-eyed man.

"Little one," Naruto said as he lifted the little Illya in his arms.

"Uncle... Are you going to leave again?" Little Illya asked as she clung more to her favorite uncle.

"Yes, your uncle has work to do," Naruto said as he kept walking.

"But you never play with me," Illya pouted as she looked at Naruto.

"At some point, I'll have time to play," Naruto said with a smile that excited little Illya.

Arriving at the mansion of the Einzberns, Naruto left Illya in the hallways, and he headed to a place only he had access to. This place was a large library, but he wasn't here for that; there was a spell that, if he managed to create it, would make him practically untouchable.

This spell would connect part of his soul with the root; he called this spell "Infinite." No one but he would be able to pass because this spell would act as a protective barrier.

Smiling broadly because with this spell, he would have even more possibilities to fight against the servants of this war.

He went to the back of what looked like a library and entered through a secret passage. Upon reaching the place, several lights turned on, and several Einzbern maids appeared; these were Naruto's personal maids and would prepare everything once Naruto woke up.

Sitting in the middle of the room, Naruto channeled a lot of mana into his eyes and began to connect them with the world's root. Every second his mana drained at great pace, the veins in his eyes began to bulge, and blood began to come out of his nose and mouth, the veins all over his body seemed to want to burst but from one moment to the next.

Infinite

He opened his eyes; in front of him were the present, past, and future, the world's root was in his power, but he urged beyond. He not only wanted the world's root; he wanted the world itself. With a victorious smile, he opened his eyes, and a myriad of information was given to him, but before he realized it, he passed out from the loss of blood.

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The city of Fuyuki was illuminated by the lights of the buildings in the center of it, but far from there, watching from the top of a hill was an individual dressed as a priest observing a mansion below him, expressionless as he had been most of the time since the Holy Grail War began.

"The church contacted me; it says that the seventh servant, Caster, has appeared."

"The last servant has been summoned? Then it's time."

"Of course... You will go ahead to the Tohsaka household."

"And once I arrive?"

"The magical barriers of the houses should be child's play for you."

"Are you sure about that? You're supposed to be allied with Tohsaka Tokiomi."

"Don't worry about that. Even if he has the face of Archer, there's no need to fear... There's no need to fear Archer, one of the three Knight classes?"

"I'll leave the rest to you! Your first mission is to kill Tohsaka Tokiomi."

And the end of the chapter.