Shirou charged in, holding his sword in a relaxed manner, he had a loose but secure grip on the sword, not applying too much force such that it would be a hindrance to him.

He thrust his sword multiple times, varying the timings between each thrust of the sword. With each thrust, Shirou aimed the sword at an angle where the glancing blow made by each of the thrusts would be returned in a manner such that he would be able to effectively utilize the momentum of the sword into increasing the force of the next.

His opponent was ready, with a steady stance parrying each and every blow with passion and force hoping to send a message such that every parry made against Shirou's sword would send a jolt of pain up his arm, allowing for a potential disarmament of Shirou's weapon,

Shirou's blows were effective, nullifying the force of the parries. His opponent was unable to keep up against the steady wave of offense, being forced to increase in speed and force to be able to redirect Shirou's thrusts.

Hoping to avoid eventually slipping up against Shirou's wave of attacks, his opponent mustered a heavy force and aimed at Shirou, directly targeting his sword, hoping to be able to overpower and knock the sword out of Shirou's hands.

Shirou was using a one-handed grip instead of using both his hands to hold his sword, as such Shirou would have been caught off guard against the offense made with the more stable grip and came out worse in the engagement after the clanging of the swords slamming against each other.

Fortunately, Shirou had gained an acute instinct through honing his swordplay and had expected it, being able to easily adjust and change his position due to using a more flexible free flowing sword form.

Shirou had redirected the heavy blow with his dominant arm holding the sword, inwardly cringing from the far superior force than what he could muster at the moment.

Fortunately, his opponent had been playing into his hands and performed as Shirou expected, allowing him to transform his opponent's slash into a glancing blow to his sword and leaving his opponent off balance due to overextending.

Smirking, Shirou had twirled his sword in a steady slash at his opponent, returning the favor.

Having delivered an effective blow, Shirou's opponent was forced to jump back in order to avoid being targeted by the sword, losing the benefit of a steady footing, without an opportunity to be able to quickly get back into position.

Frustrated with the strategy that Shirou had utilized, his opponent had decided to go on a furious offense consisting of wide slashes movements telling a story of a beast in rampage. His opponent had hoped to be able to get back the advantaged that she possessed but was denied as Shirou was once again prepared.

Shirou had held his sword coolly, unruffled against the fiery aggression that his opponent was displaying.

He swatted away the blows like flies, his talents in swordplay obvious, handling the physically superior opponent with ease. He quickly spotted an opening, a gap in the furious onslaught that had been meant to defeat Shirou.

He quickly caught an opportunity and slashed his sword at the back of his opponent's blade on a thrust, the force granted by the superior leverage in position allowing for Shirou to quickly disarm his opponent without much fanfare.

Shirou was satisfied. While Shirou was not an arrogant individual, he was always pleased for a win. It had resulted in much of a relief when Taiga had proposed the resolution of arguments on a kendo duel. Shirou had been rather surprised when Taiga had wanted to invite all the children within a square mile and throw an exorbitant party for Shirou's birthday.

Hadn't that woman known that Shirou was antisocial? He had no desire to spend time around anyone, much less strangers on a day that was his birthday.

Shirou inwardly shuddered at having to spend most of the week around other children of his age, he had felt an aversion for children of the same age after being convinced by Taiga to go to the park.

Taiga had said it would be 'fun and educational'. Shirou snorted, trust his naïve self to believe her dastardly lies. Well… it was rather good to get another victory over Taiga, Shirou could have sworn he had seen a vein threatening to burst through his sister's head with every subsequent defeat to the ten-year-old…

Shirou had been an oddly mature ten-year-old, it had seemed that the events of the fire may have had an impact on that, an outside opinion may have been that it was due to Shirou's fixation on swords and swordplay. Then again, Shirou supposed he would not suffer too much, he had somehow been oddly gifted in subjects consisting of theories such as math and science.

He did not enjoy the subjects but had yet been oddly competent in grasping the concepts quickly. Shirou had chalked that achievement up to his boundless curiosity in trying to master every concept and theory he was aware of.

Inwardly, Shirou had wanted to conduct more experiments on his magecraft, having hounded Kiritsugu to hunt down books on magical theory and convinced him to give him a complete lesson on the principles of bounded fields.

Kiritsugu apparently was an unofficial but undoubtably world class expert with regards to bounded fields, especially in the theoretical aspect on penetrating bounded fields.

Kiritsugu had mentioned that it was better to make sure that the field was airtight and at least notified the owner against everything rather than actively attack all intruders and risk tripping off the intruder and allowing them an opportunity to prove the defenses inadequate.

He had even spent several days teaching Shirou the best ways to set up bounded fields, he had looked strangely exhausted after such a meager use of magecraft.

It had seemed that Kiritsugu was more open to teaching Shirou Thaumaturgy recently, it might have been due to Kiritsugu being exasperated about the fact that Shirou was too absorbed in the magical world to want to live a regular life or Kiritsugu believing that Shirou could handle and survive himself in the cutthroat world of magi especially after the incident of Kiritsugu finding a Noble Phantasm in his shed…

Shirou had been able to improve the process of Graduation Air. He had gone down a natural path by following what would improve the spell normally. Holding a more detail image of the materials one intended to project and layering them together while keeping in mind an exact structure.

Shirou had simplified this process by inserting the usage of several extra steps into the spell. Fortunately, the Magical Formula of the spell had granted him enough leeway that the spell had still worked. Even better, what he had set out to do was successful.

Shirou had been able split the process into seven steps that delved down to the fact that he would first question the existence of the object and aimed to project the object with a degree of purpose into the world. He would then start holding the basic structure, materials and manufacturing process and skill involved in the process in mind when projecting the object. He would then attempt to provide an artificial history of the object and go through the steps again to ensure perfection.

It was with these steps that Shirou was able to produce a more stable object that was able to last longer, be more sturdy and undergo lesser rejection by Gaia since it was able to fool the mother earth into the sensation that the projected object had been produced naturally rather than through the usage of magecraft.

The breakthrough had come from an experiment on projection in trying to recreate the Musashi Masamune as a showpiece and unintentionally thinking about the full history of the sword from forging till the current day.

Shirou was startled about the sudden disappearance of a large portion of his mana reserves when he realized that he had made a startlingly surprising near perfect recreation of the sword. He was even more astonished when he saw the sword still there a day and a half later.

A dozen days of experimentation later and Shirou had been able to conclude that by instead of simply projecting the sword or a visual of the sword, he had rather recreated the sword in its entirety, making it not just a simple projection but rather recreating the Noble Phantasm from scratch. Shirou later called this superior version of projection magecraft tracing.

The few times Shirou had recreated the legendary sword, he had been spent, spending a large amount of energy compared to a regular European longsword. He had noticed that the sword while a near identical recreation, had not possessed quite near the intense aura of quality that had been emanating from the original.

Shirou had concluded that rather just recreating the workings of the sword, the tracing spell was able to not just remake the sword through the imitation of its materials, but also directly remake the forging methods and the skill involved in the forging of the sword.

Shirou was able to also reinvent the history of every wielder of the sword while tracing the sword, effectively also allowing for a creation or simulation of a completely new timeline for the traced sword, solidifying its faux existence within the world.

Shirou had also been astounded that when using the traced sword, he was also able to replicate the skill of each and every owner that had held the sword.

He was in awe of being able to reproduce the skillful strikes of the sword saint. He had discovered that it had resulted in a massive stress carried out on his body when reproducing the skills due to not having the reflexes and muscle mass required to carry the skill out.

It was lucky that from the first time he had glanced at the genuine article, he had obtained enough that he had now been able to perform his own version of that swordplay to a reasonable level.

Having created the new spell from an advancement of projection, Shirou was interested in fully developing the theory behind the spell, he theorized that if he was able to imitate the skills and habits of the most prominent holder of the sword, he might be able to reduce the cost in remaking the sword since the magical cost for tracing would not have to imitate as the skill of the owner as much.

What was alarming was that since what he had done by gazing at the sword was akin to owning the memories of the owners, he had started to take up some of the habits. However, taking up the habits of the sword saint was not a big deal to Shirou, he had been an avid admirer of his swordplay as well as combat philosophy.

While practising one of the habits of the sword saint, Shirou had observed that when casting magecraft shortly after meditation, he had been able to absorb and gather more mana from the outside world into his circuits.

The mana he had gathered was also of a denser variety, thus able to allow him to conduct more expensive mysteries such as tracing with less mana cost and also with greater effectiveness and efficiency.

Shirou had at first been rather perplexed at this turn of events, he had quickly locked down the possibilities such that he had ascertained that the reason for the difference in magical energy was due to his breathing patterns shortly after meditation.

He had concluded that this was a realization of an eastern philosophy into Thaumaturgy in the form of 'Chi' and that by synchronizing his actions of inhalation and exhalation with the flow of nature, he was able to connect with the surroundings around him, allowing for a better absorption of mana from the outside world.

He had theorized that in many eastern legends, due to breathing and walking in a certain calm manner being a focus on martial arts, the warriors are subconsciously absorbing mana of a higher quality and creating mysteries, thus allowing for many famous and renowned warriors of eastern culture to be able to move at a level higher than a regular human by enhancing their body allowing for perhaps better result than would have been gained by using the spell of reinforcement with the knowledge of Thaumaturgy.

Shirou had proven his conjuncture that by using the denser mana gathered by this method, he was able to trace a higher quality version of the Musashi Masamune, allowing it to be able to survive for a week before undergoing rejection by Gaia. It appeared that the higher quality magical energy gained from the conversion had enhanced the quality of his magecraft.

It was the product of this superior result of tracing that one day in cleaning up the shed, Kiritsugu had been able to uncover the synthetic noble phantasm lying around in his home.

It had resulted in a short confrontation in which Shirou had not been too against revealing his full progress of his advancement of magecraft to his father, wanting to take advantage of the opportunity to promote more confidence in the older Emiya, hoping for him to relent and allow Shirou to undergo more instruction in Thaumaturgy.

While Kiritsugu was extremely shocked at his son's progress in magecraft, he had determined that Shirou would be able to keep safe in the magical world even with the risks of carrying the Emiya name. He trusted that his son had adequate instincts as well as decent skills at combat at his age even when he was not specifically seeking out skills to master for combat.

The Magus Killer had a hunch that no matter what would happen, his son would eventually be embroiled in the world of Magi. As such, perhaps it would be better if he were able to instruct Shirou more on the practices as well as general knowledge of the world of Magi.

The older Emiya had also taken notice of Shirou's talent and skills in swordplay and had also taken to sparring with Shirou more often with more brutal tactics than what he normally used. He had hoped that this would help him down the line.

Shirou supposed that this display of tough love was perhaps Kiritsugu's way of subtly informing Shirou about the dangers and reluctant approval of Shirou to be involved in the hidden world.

Shirou was concerned about his father, he had been looking more haggard as time went on, he seemed to be declining in health for some unknown reason. Shirou had assumed that Kiritsugu had relaxed in his personal fitness after retiring but it was apparent that it was not the case here.

At first Shirou had not noticed the symptoms, but kiritsugu had been losing weight and as much as his father tried to hide it, his father was having more trouble in his daily activities.

Shirou was helpless, as far as he could tell, there was nothing visibly wrong with his father. His father still possessed a healthy appetite and he had not gotten sick nor shown any symptoms of sickness.

Shirou had a hypothesis, he believed that the incident shortly before Shirou's adoption that had gotten his father to retire could have been a factor with Kiritsugu's health decline. Shirou however lacked a solution, confronting his father would have been useless for there was nothing Shirou could do to help and it would have provided an additional emotional burden for his father to take.

He was under a schedule however, it was nearing the time of year in which his father would make his yearly trip to Germany. His father had always come of worse after those trips yet Shirou had no confidence in being able to inhibit his father's plans of travel.

He believed he had a limited time to save his father, he did not assurances that his father would be able to survive subsequent trip after this. This indicated that if Shirou were to possess any hope that his father would be cured, he would have to go behind Kiritsugu's back…

Shirou had no indication on Kiritsugu's affliction however, Shirou had an inkling that the illness was related or caused as a result of magecraft. From the meager number of books on magical theory that Shirou had convinced his father to source, he had a suspicion that Kiritsugu was suffering under a curse.

Shirou did not have much information on the supposed curse being placed upon Kiritsugu, but he doubted that Kiritsugu had been cursed willingly nor that he had been placed with a curse to atone for his actions.

The young Emiya was rather curious about the nature of the curse that his father was under. While Kiritsugu was not the best magus, he was nonetheless a practical one, if Kiritsugu was under a curse, the young Emiya doubted that Kiritsugu would eventually be able to get the curse off him, while Shirou knew his father was empty, he doubted that Kiritsugu would kick the bucket willingly until whatever Kiritsugu had over in Europe was settled.

The son of the Magus Killer had even resorted for searching in books of mythology, and folktales. The tales were simple and had not been specific enough to bear a resemblance, Nonetheless, Shirou knew that more information would only help in his new quest. None of the curses contained even seemed like it was similar to the one that Kiritsugu suffered from.

This meant that Shirou had to get outside help, while he had no doubt that Kiritsugu had connections in the magical world, he himself did not know enough to seek any sort of help. He doubted that the clocktower would accept a random Asian Magus so that meant looking nearby.

As part of his education on the magical world under Kiritsugu, the Magus Killer had informed Shirou on the location of Magi in Fuyuki. He had especially cautioned Shirou away from several figures such as Zouken from the Matou family as well as the church. Kiritsugu had seemed especially wary of a priest named Kirei Kotomine.

This meant that the only option left was the Tohsaka's, of which the only one remaining was a young heiress of the same age as Shirou. This meant that while she would probably be no help, on the other hand her family's Mansion had likely still contained a library with books and information that would be of help to Shirou.

Shirou was in a quandary however, even if he were to get into contact with the Tohsaka heiress, he had had nothing to be able to enable him to be able to convince her to provide use of her family library nor did he have any leverage that could be used.

While Shirou's curiosity had lessened over the years, he was still an inquisitive individual. He had managed to rein in his impulses and had given Kiritsugu his due privacy after his discovery, but he had convinced himself that he would have to once more take up the habit for the benefit of his father.

Shirou had never went looking in Kiritsugu's notes before. He had been aware that his father had an acute habit of keeping notes of his life's progression in the form of dairies but as far as he was aware, most of Kiritsugu's more recent notes across the last five years had been around the research of bounded fields.

Giving a quick browsing of Kiritsugu's notes, Shirou observed that most of Kiritsugu's research into bounded fields has been around taking them down. Shirou had known that Kiritsugu was extremely familiar with bounded fields due to his past occupation but he was aware that the Magus Killer had always taken the more pragmatic way of trying to find loopholes as a method of getting around bounded fields than directly taking them down.

It was a good approach, the young Emiya mused, however that did not discard the fact that his father had extremely profound research into the bounded fields and the methods of taking them down. It was a lot more knowledge than what Kiritsugu had required in his past operations.

The research of bounded fields by Kiritsugu was also scarily revolutionary, it appeared that rather than just having the ability of taking down bounded fields, Kiritsugu was researching into techniques that would increase the speed and efficiency as well as drastically reduce the cost in magical energy involved in taking them down.

Not placing too much importance on the research of Kiritsugu, Shirou continued looking within his father's notes. He had prioritized looking for documents that involved the Tohsaka family for leverage as well as looking for documents that dated back to the incident that had likely caused Kiritsugu's affliction.

It was fortunate that Kiritsugu had catalogued and organized his notes on an orderly manner with time frames and code names but there was little mention on the Tohsaka's. What little that Shirou had been able to find had been on documents related to a German Magus family called the Einzbern's. It appeared that his father had been employed by the German family.

Not that Shirou had cared too much about the Einzbern's but he made a mental note to research more into the Germans, having an inkling of suspicion that the purpose of his father's yearly trip to Europe was related to the prominent Magus family.

Shirou was aggravated, he had gone through almost all of his father's past missions and learning more of his father's operations than he had needed to know.

His father had spent most of his time working under magical organizations based in Europe, it had seemed like the majority of the magical population was centred in Europe, it appeared that the majority of fame the Tohsaka's possessed was due to having relations with the second magician, Kischur Zelretch Schweirnorg as well as being heavily involved in a ritual called the Holy Grail War.

Fortuitously, his dad apparently had dealings in this 'Holy Grail War' it seemed that his father was heavily involved too, considering that there was an entire drawer's worth of folders relating to the 'Holy Grail War'.

Shirou opened the first folder of the Holy grail war. It had contained the history of the war as well as the past results of previous wars. Apparently, there had been four wars so far with the last being the fourth. The folder sated that the primary purpose of the war was to enact a ritual through a loophole that allowed the exploitation of the root to grant near unlimited amounts of magical energy in order to be able to grant a wish.

There had been three main Magus families that had participated in the war. The Einzsbern, Matou or Makiri and the Tohsaka. The folder was labelled and categorized with footnotes linking to other folders on the Holy Grail War. Shirou skipped the rest of the document on the history of the war and went to the folder containing the information on the Tohsaka family.

Due to the knowledge of the Tohsaka's, they could be a large threat in the process of summoning the servants, while attempts at subverting the Grail are unlikely to occur, it is a likely possibility that the Tohsaka's may be able to summon a servant of A rank or higher.

Shirou flipped the page, judging Kiritsugu's personal thoughts on the Tohsaka's to be of irrelevance.

Tokiomi Tohsaka has secured an alliance with the church represented in the war, two servants serving on the Tohsaka side of the war is extremely likely. Threat level greatly increased for Tokiomi, more monitoring is required once the war begins.

Shirou continued on the page, wanting to see Kiritsugu's findings on the monitoring of the Tohsaka family.

Assassin appears to be eliminated by the Tohsaka servant in an attack of the Tohsaka mansion. Doubt is present on the true state of servant assassin, consider possibility of planned deception if assassin is summoned by Kirei Kotomine…

The bounded field of the Tohsaka mansion has been penetrated, Tokiomi Tohsaka is found dead. The probability of a servant killing Tokiomi is low, Kariya Matou does not fit in the timeline to be the one who eliminated Tokiomi. Likely suspect is Kirei Kotomine…

Kirei Kotomine is still in the war, servant assassin is dead, probability is high that Kirei possess the command spell for archer. Kirei Kotomine has inherited the custody of the Tohsaka holdings, assume possible agenda for killing of Tokiomi. The likely custody of the Tohsaka heir is held by Kirei…

Shirou smirked, closing the folder. He had obtained exactly what he needed, now he just needed a way to approach the Tohsaka heiress alone. He was slightly displeased at having to resort to such methods but he payed the line of thought little attention, he believed that if his father was aware, he would have admonished Shirou for placing an importance in honor.

Shirou gathered a pinch of magical energy from the surroundings and used structural grasping on the folder, memorizing and scanning each and every inch of it. He would need a high-quality long-lasting projection of the folder when the time came.

Now, Shirou supposed he better clear up the mess he made in his search. He reopened the drawer and relived several other folders out of it. Time to find out what the fuss about the Holy Grail War was about, Shirou mused…

Authors notes:

Firstly, we get to see Shirou's progress in his sword skills, this chapter starts two years from the last and we get a glimpse of the personality that Shirou would eventually develop into. Currently the most important this to him is his research and curiosity because of his Origin, which sorta gives him an instinctual understanding of everything theoretical. It is not a information dump into Shirou but rather a nudge telling him whenever he studies something theoretical that "this is not complete, it can go more, there is a higher stage". As such, due to Shirou feeling that something isn't 'complete' his curiosity triggers in and makes him want to research the topic to the max.

Shirou currently has the canon relationship he has with Taiga but he disdains the childlessness of her more. In this cause Shirou is a bit Tsundere'ish as in he disdains her on the surface but holds affection for her antics. He is however very socially stunted, do not expect him to make many friends.

In this story Kiritsugu recognizes Shirou's talent in magecraft, has an understanding that since he can't keep Shirou away from the magical world, might as well make him as safe as possible. He also knows that as Shirou is still ten, he does not train him since he wants him to be able to have a childhood.

The development of Shirou's magecraft with the spiritual eastern belief of mediation and breathing and walking thing is not my invention, it is used in canon to justify Kuzkui's better than human reflexes and perception as well as speed pre-buff by caster. I also thought it would be a great idea to explain eastern heroic spirits since all of the regular western based heroic spirits have awareness if not use of magic in some way and with this explanation, it allow eastern legends to break human stats and stand on an eastern ground. Also I would need Shirou to be able to gather denser and more mana for his magecraft in the future anyway, plus this gives him an interesting boost to be able to compete without constantly reinforcing himself.

Shirou becomes aware of the Holy Grail War, he also knows about Kirei's murder of Tokiomi Tohsaka so that gives him an interesting excuse to get into contact with Rin before entering Homurahara academy without something stupid like meeting at school. Also, I haven't yet seen a Rin that is aware of Kotomine's nature before the Holy Grail War so that also provides an interesting avenue of development.

This chapter is the most exciting setup for Shirou to interact with Rin as the typical fanfiction is just Shirou rolling over for Rin or Rin just being a regular Tsundere. An earlier meeting with both individuals at age ten and Shirou making use of Rin is a fascinating storyline that I would like to explore. Since there's still seven or so years till the war I want to explore Rin having a different Goal for the Holy Grail War without the vague I want to achieve victory for my families honor shallowness.