Later on, in the evening, Jack sat in his room in deep thought. During the previous night he'd realised there was a rather fatal flaw in the way he'd been training up to this point. In fact, it was so fatal that he almost wanted to slap himself in the face for having neglected it.
The problem was that he'd been wholly reliant on the Harmony of Everything and had tossed aside the very basics of martial arts: technique, discipline, and control. The Harmony of Everything was an incomparably tyrannical cultivation method that boasted rapid advancement speed and superior strength to martial practitioners at the same level, but its true might wasn't that fact; rather, it was its ability to incorporate any technique into its cultivation.
As its name implied, anything could be harmonised through it.
However, Jack had been concentrating too much on the method itself, ignoring its ability to accommodate any technique into its repertoire as long as the practitioner trained it. This, coupled with how unfamiliar his body felt, ultimately meant that he was far from the technical proficiency he was so proud of during his time in the Abyss.
To remedy this shortcoming of his, Jack knew he needed to choose a few techniques to begin practicing in order to fully familiarise himself with the state of his body and properly exert the right amounts of strength at exactly the right timing.
Before he began cultivating the first chapter of the Harmony of Everything, he needed to raise his technical proficiency to the degree wherein he could easily overpower opponents of a higher realm of cultivation.
The reason this could be achieved by practicing a few techniques was firstly by experiencing the flow of qi from his meridians; secondly, to show him how much energy he'd need for a given movement at any time; and thirdly, to break into his new body by testing its limits and interiorising the information.
To put it differently, the Harmony of Everything turned his body into a massive reservoir of water. Without the proper tools to extract that water and channel it to the right places whenever necessary, the reservoir itself wouldn't be half as useful as it could potentially be. By practicing advanced combat and martial techniques, he'd effectively be giving himself those necessary tools to fully use the power within the Harmony of Everything.
As such, Jack was deciding on what techniques to focus on.
Martial techniques were wholly different to cultivation methods, although one couldn't exist without the other. A cultivation method was a means to draw and store qi within one's body, proceed and break through higher realms of martial practice. A martial technique used the qi within the body to power itself. The stronger the technique, the more qi it required.
In addition, martial techniques all had several realms of mastery that a practitioner needed to break through in order to draw out more power from the technique. These were divided into five levels of mastery: initial, intermediate, upper, advanced, and perfect. To break through the levels, each technique had its own requirements and conditions; but they all shared in common that it was only possible when there was a breakthrough in comprehension involved.
To give an example, Jack had once read of a technique called the Thirty-six Palms of Chaos. At initial mastery, the one who trained this technique would strike out with one earth-shattering palm strike. At intermediate, the user would strike with up to six palms, then thirteen, twenty-two, and finally, once perfect mastery was achieved, up to thirty-six palms could be used to utterly destroy an opponent.
Of course, there were many ranks of techniques depending on how powerful they were and how effective they could be in combat. The higher the quality of the technique, the stricter were its requirements to practice and fully cultivate to perfection.
The widespread means of ranking the quality of techniques was divided in several tiers; those being: human, earth, sky, transcendence, disaster, heaven, saint, supreme, and cosmic. Each of these realms was further divided into four levels, mainly lower, middle, higher, and peak.
Thankfully, during his time in the Abyss library, he'd been in contact with thousands of amazing techniques of various degrees of power he could now put to use. Back then, he'd been stripped of his cultivation and so he hadn't had the ability to train them, but now he had the chance to do so.
He began rummaging through his memories and going over them in his mind, discarding techniques that weren't appropriate for him or that they demanded a much higher cultivation base before he could even look at them. That excluded all saint tier techniques and upwards.
After a few hours of careful selection, Jack finally assembled an assortment of seven techniques that he wanted to train in and which were extremely compatible with his present state and situation.
The first was, of course, the Exploding Fist; a higher disaster tier technique. He chose this technique partly because he already experienced it previously and, secondly, because besides its astonishing power output, it also had the added advantage of it being capable of helping him train the flow of qi throughout his body.
The second was a movement technique called Shadow Steps; which belonged to the list of intermediate disaster tier techniques. Shadow Steps was useful in close quarter combat as it allowed for short bursts of movement so swift, that when it was practiced to perfection, left afterimages behind that confused the enemy and allowed for tricky engagements and attacks at an opponent's blind spot.
The third was another movement technique that combined with shadow steps beautifully and completely negated its shortcomings called the Azure Dragon Step. This movement technique was a whole tier higher than Shadow Steps, being an intermediate heaven tier technique. The Azure Dragon Step allowed its practitioner to move like a dragon, twisting at impossible angles and changing positions seemingly without any sense or pattern. In addition, it was useful for moving with the speed of a true dragon over long distances when mastered. This technique would be useful to Jack both inside of combat and when travelling all over the world.
The fourth was a series of sword arts similar to the Japanese style iaido of the peak disaster realm. This was the Quick Draw; a set of movements wherein to quickly, yet effectively, cut down opponents with a simple draw of the sword by aiming at their vitals with speed that the eye couldn't follow. If you added profound qi and Jack's bodily strength into the equation, then the speed with which he'd strike out would be more than destructive.
The fifth was also, in a sense, a weapon art, because it didn't really focus on any weapon in particular. In fact, its main teaching was to turn every bit of the practitioner into a weapon capable of harvesting life on the battlefield. With it, a practitioner could break swords, splinter shields, and tear through armour with their bare hands. Its name had also been lost to the passage of time, but Jack had baptised it as the Warring Claw. This technique belonged to the higher heaven tier.
The sixth wasn't a technique he'd obtained by himself in the Abyss library. Rather, it was something Belial had rewarded him with roughly one thousand years after he arrived at the Abyss. It was a higher heaven tier technique called the Revolving Trigrams; a series of finger strikes aimed at the different acupoints of an opponent, allowing for crippling effects with the mere poking of a finger at the right place.
This was the technique he'd used against Hannah and her father the previous night, but he wasn't proud of his performance with it.
Jack chose to re-cultivate this technique firstly because he'd already mastered it to perfection in the Abyss after using it for thousands of years. The only factor impeding him from reaching that level right then and there were his bodily limitations. Secondly, this was a technique with an amazing potential for medicine and other positive effects that he hadn't had the chance to explore whilst in the Abyss. The main reason, however, is that he would be able to triumph over enemies far greater in size than him by striking at their weak spots in ways they couldn't even begin to fathom.
Finally, there was the seventh technique. From a certain point of view, this was the most important and powerful of the techniques Jack had chosen. Its name was Absolute Vision.
It was a mental technique that focused on one's eyes and enhanced them in order to see the flow of qi within a small radius around the practitioner; and it required them to first learn how to perceive the flow of qi using their spiritual sense and then drawing their soul strength into their eyes to turn that spiritual information into a visual one.
The advantage of this was two-fold. Firstly, it would allow whoever trained in this method to cultivate faster given that they could see the flow of qi in the environment; which could also mean seeing where spiritual herbs were growing, given that there was usually a heavy stream of qi surrounding them since they absorbed it to grow. Secondly, when the technique was trained to greater levels, the practitioner would be able to see the flow of qi within the body of their opponent, meaning they could anticipate attacks and even counter them before the opponent ever had the opportunity to strike.
What was most peculiar about this technique was that it didn't have a set tier that it belonged in. In other words, it grew alongside the user and could, theoretically, reach the highest tier possible tier alongside the user. However, Jack had no concrete evidence of this beyond his own impressions from when he discovered the technique deep inside the Abyss Library, in an extremely well-concealed and closely guarded section of it.
Overall, he was very satisfied with his choices.