Of course, the new use of Personal Library that he had discovered was not the only piece of his combat prowess he was showing here. Unlike Julie who lived and breathed combat for the majority of her life, Jien's own experience was in the last few years. He had gotten a better battle sense in those years over a multitude of fights, but it wasn't an instinct like it was to Julie. Instead, everything was a calculation and a chess game. The more exact the move the better without exception as long as loss was minimized.
He had taken his sword instructor Emily Bujrim's words to heart and built his fighting style on it. 'Precision in all things' was the motto of this very technique right now. The concept was simple, he had learned puppetry from Runa for use with his sword style. Puppetry from an arcane sense wasn't far from that of marionettists who didn't rely on the arcane arts. You simply moved the strings attached to certain limbs in a specific order to move a puppet in a specific way. Though finer control was needed for smoother movements at it's basics the concept was simple.
Jien took it from use on his sword to use on his own body. He knew that while he was getting better at his combat skills with every fight and every challenge, his strong suit was as a strategist and likely always would be. He wasn't against fighting when it was needed but that didn't mean he enjoyed endlessly swinging his blade in search of enlightenment and muscle memory.
After finding subset of his personal spell that he nicknamed his 'Combat Library' he had thought of a few useful ways to use this new skill and information it contained. If he could record the combat prowess of others for review, could he use it to simulate what it was like to fight someone before a fight? The answer to this was not without either having a catalog of their fighting style already or knowing enough about it to match it up against others.
However, what he did find was that based on the start of a person's technique or their stance he could roughly match them to previous fights in a loose way. And in this way, if he knew the weakness of one foe in a similar stance it could show him the potential weaknesses of the one in front of him. The only issue with this was that the translation was loose so not every fighter would actually have the same weaknesses. To prove this point his mentors had beaten him and his friends senseless more than once for targeting either false weaknesses or those they showed as a trap.
This story is posted elsewhere by the author. Help them out by reading the authentic version.
The next piece of the Combat Library, and most crucial was Jien's discovery that if he concentrated on it with all he had, he could overlap the image of another fighter and himself. This became akin to giving him a tutorial on how to adapt a fighting technique. Everything from the stance to the shift of the muscles and the movement of the weapon were all recorded, he just needed to be able to follow it well.
This became a wall, and an insurmountable one, at least in the short term. Sure, he could practice these stances, the methods and the styles of everyone he recorded but only if he could get the movements correct. This would be useless in a fight if he use of a technique in a fight was so sloppy that it was easily countered or used against him. Not only that, but transitioning between them was near impossible.
It was when he was discussing this with Runa during their break after that year's punishing expedition into the Warping Forest. She pondered on it for a while before asking him a simple question. "Would it work if you really could follow along with those movements perfectly?" This led to a long line of discussion with his handmaiden on what would or wouldn't be possible using this method. The results were that if he could it would give his fighting style a large amount of variability and finesse, but that his lack of experience was his truest barrier.
The next morning Runa joined him out on the training field, telling him that she had thought of a solution, but that it wouldn't be easy to grasp. At first the solution sounded ridiculous, to use oneself as a puppet and force it to move as needed. However, the more Jien thought about it and worked out the theory behind it with Runa's help the more he came to realize just how possible it was.
The biggest barrier he found in the entire discussion actually turned out to be his body rather than his fighting experience. When he attempted the method for the first time he nearly dislocated his arm at the shoulder, elbow and wrist while trying to complete a simple parry that Emily showed him in a short lesson, having come back each time he had a break to check on the heir to her sword style.
His body wasn't flexible enough and even beyond it the body would instinctively fight the external input of the mana strings. Perhaps it was more the mind than the body that would fight it, Jien wasn't sure. What he found out though, was that while the first problem was easier to fix the second was near impossible to fight against naturally.
From the day he nearly dislocated his arm he worked relentlessly on his own flexibility to the point that he baffled his friends. They couldn't understand why he focused so much on stretches that he abandoned other types of physical practice all together. That was, until they saw it for the first time. He was able to suppress his internal instincts just long enough to complete a single parry and thrust just like the one he had just now completed against Julie. The precision and ruthlessness shocked even his mentors, but he found himself unable to replicate it a second time until months later.