In Mushoku Tensei with an A.I. Chip

Luke faced his opponent, the Sword Saint Grant, in the middle of the training grounds in Notos Keep. 

He had just completed scanning all of the ingredients the Notos procurer had acquired on his behalf yesterday, which had taken a few days to complete with so many herbs, plants, powders and monster parts to scan. Now the A.I. Chip needed a few more days to complete its analysis of the ingredients. 

While waiting for the A.I. Chip to complete its task, Luke went back to his regular routine, which included sparring with the three Saints in Notos employ. 

He had begun sparring with his swordsmanship instructors using magic ever since he hit Advanced rank as a magician. In the beginning, it was pretty rough. He had retained little of the Original's experience in fighting and combat that were lost along 83% of his memories in the aftermath of his journey across the Astral Plane. Luke essentially needed to start from the ground up to build back up his skills. 

Additionally, his limited mana reserve held him back so even when the Saints were holding back, his methods were limited when he could only fall back on Elementary and Intermediate spells. Advanced-rank spells cost too much mana, and using just one or two would leave him fatigued and nauseous. 

He was only six and a half then, so give him a break. 

But as his mana capacity kept growing, and his instincts sharpened through repeated sparring, Luke started to hold his ground even when faced with Saint-ranked swordsmen. 

In their defense, Grant, Ward and Bernard were skilled knights in their own right. But they naturally didn't have any experience fighting a magician who could instantly and silently cast spells. Not to mention said magician was a combat genius who improved drastically after every fight. 

After action reviews with the A.I. Chip's recording and analysis functions allowed Luke to dissect every aspect of the spar. What he did right, what he did wrong, what he could have improved on and alternate strategies to consider. 

Furthermore, after having spent more than a year playing with and experimenting on the magic of this world, Luke had come to a fortuitous realization. The magic of this world was shockingly malleable. 

In the Magus World, spells were held together almost entirely by a spell model. Spell models were the matrix of a spell, and the process of casting a spell entailed the construction of a mental model of the spell utilizing one's spiritual force. Subsequently, external energy particles would be attracted and in the process be transformed into a spell. 

The spell model was the mould and catalyst of a spell, without which it was impossible to cast said spell.

It was different here. 

Mana was the fuel, and the caster's will and spiritual force was the guide. As long as the caster understood how to circulate their mana correctly, according to the spell effect he wanted to discharge, then that was everything they needed to cast a spell. 

What did that mean? It meant that Luke had already 'invented' hundreds of new spells over the course of his three years learning magic in this world. Naturally, not all of them were practical to use, but all of them were useful at least for research purposes. 

With his ever-expanding repertoire of spells every fight against Luke was akin to facing someone completely different every time for Grant, Ward and Bernard. In one fight Luke could demonstrate a dozen different Fire spells, and in another Luke could reveal a dozen different Water spells. 

The three Saints working for Notos Greyrat learned from their spars as much as Luke did, perhaps even more. Being placed in intense stimulation for so long through their spars with Luke, all three had startlingly realized their stagnated skills and techniques were starting to improve again!

Grant, the strongest of the three, even thought that he could possibly break through to the level of a Sword King soon if he kept up this level of extreme stimulation!

Secondly and thirdly, sparring with the knights proved an effective method of expending his mana reserves to raise his magic power, and it was also a good platform to test his invented spells. 

"Are you ready, young master?" Sword Saint Grant asked, more for his own sake than for the young noble scion. Grant had never not known his young charge to be anything other than ready for anything. 

If anyone had told him he would actually be losing spars to an eight year old, or a seven year old as was case when Luke had defeated him for the first time, Grant would have laughed in their faces before bringing them to a healer as they would obviously be ill in the head for suggesting as such. 

Luke nodded, "You can have the first move, Grant." 

It would've been an insult had Grant not known what the lordling was capable of. He never knew a more terrifying opponent than the boy before him. 

Even the Sword God, who Grant had seen in action once before, was not as scary. Gal Farion had been overwhelming. Simple, but fast. Faster than his own eyes could comprehend. But Grant at least knew how the Sword God could do what he did, even if he himself could not replicate it.

But Luke's monstrous growth was unfathomable, and Grant literally could not comprehend the depth and breadth of Luke's true potential. The incomprehensible was naturally far more terrifying that the fathomable. 

The Sword Saint leveraged the offer by immediately gathering Touki in his limbs and then exploding forward in a blur of movement. 

The Longsword of Light is considered the ultimate technique in the Sword God style. All force is concentrated into a single swing that is meant to be the only swing needed to end a fight. 

It is the technique that separates mere practitioners of the Sword God style, and those dedicated to its mastery. Learning the Longsword of Light means reaching Sword Saint level. 

According to the Sword God's philosophy, if you can't win after unleashing this opening move at your best, then you have already lost. 

One would think that the bodyguard of a nobleman would not risk the health and life of their charge by using such a deadly technique right from the start of a spar of all things. After all, a single misstep and Luke's head might fall off, accident or no. 

In truth, Grant had similar reservations in the past. At least until he became increasingly familiar with Luke's prodigious skill and monstrous talent. Both of them knew that this opening move was only a feint, distraction or tee up. 

In the split second it took for Grant to halve the distance between them, Luke had already cast his first spell, followed up by a second and a third in the same moment. 

A extremely bright flash of light emerged from Luke's chest, blinding the Sword Saint and forcing him to shut his eyes. But Grant's trajectory was already set. Aimed towards Luke's neck, his steel blade glided through the air with extreme speed. 

But Luke's second and third spell triggered immediately after the light. 

First, all sound was immediately muted within the arena. Second, the earth beneath Luke's feet moved the spellcaster away from Grant's Longsword of Light. 

Blinded and deafened, Grant suddenly lost all methods to visually or audibly sense his opponent, and there was no way Luke would let himself get struck by a mere opening move. 

But he could feel the ground beneath his feet rumbling. A mistake? Regardless, it was a chance. 

Grant pivoted on his foot without losing any of his momentum, resulting in a crater that formed from the twisting of his foot, and dashed towards the source of the rumble. The initial longsword of light that had yet to be released now unleashed at the unseen enemy. 

It was all the strength and Touki Grant could unleash in a single swing that carved through… nothing. 

The theme of today's spar must be sensory deprivation and deception, Grant realised with a curse. 

But now that his eyes had recovered a little, Grant opened his eyes and was stunned. He clearly opened his eyes and yet… why was it still dark!? 

"What is that?" Selena, Luke's mother, asked while watching with Bernard from the sideline. 

Selena had been fearful for Luke when he first started sparring with the Notos knights. Nowadays, she just cheered him on from the side as he kicked their asses. 

"I'm not sure madam." Bernard answered honestly, looking at the semi-sphere of darkness that had now appeared on the field, enveloping both Luke and Grant within. 

It was obviously something that Luke created, and he had done so immediately after avoiding Bernard's first strike, releasing a thick blanket of viscous black smoke that expanded to cover the training ground almost entirely. 

Bernard wondered how he would deal with it if he was in Grant's shoes, though thankful that he wasn't. As a North Saint, he had more tricks up his sleeve to deal with Luke as compared to Grant and Ward. The North God style demanded versatility and adaptability after all. 

But even then, he lacked the sheer offensive power of Grant, the Sword Saint, and the survivability and defensive capabilities of Ward, the Water Saint. So Bernard in truth had no distinct advantage compared to his fellow guards. 

Nowadays the North Saint Bernard was starting to dread, yet at the same time looked forward to competing against the young master. He would always learn something new whenever he fought the infinitely versatile magician, but the seemingly endless ways Luke would come up with to torment them on the training ground was borderline cruel...

Back in the sphere of darkness, Grant gritted his teeth as he settled into a rare defensive formation. He could suddenly feel the slight rumbling of the ground beneath him from a dozen different sources as though there were a dozen opponents running around him. 

Truly, the young master was an insidious opponent…

Left without choice, Grant gathered his Touki and released a horizontal swipe that cut through all dozen sources of vibration at once. He raised his eyebrow when he felt the resistance of sword meeting flesh. 

Could it be?