Time quickly passed as Rui's life took on a bit of a routine. He would teach Senior K'Mala and Senior Ceeran about mathematical concepts, the theoretical framework of the atmosphere, and the classical wave theory. Senior Ceeran had already read up on the theoretical framework in the time after Rui had submitted the technique to the Martial Union. Thus, he was able to follow Rui's classes better than Senior K'Mala.
The latter found Rui's training vastly more difficult than she had ever imagined. She found that she had come across a problem that she couldn't just overcome with hard-headed perseverance. She needed to exercise her patience in trying to overcome difficulties with problems that she had never even fathomed before.
"You failed," Rui stated calmly as he scribbled crosses across a sheet.
Senior K'Mala's eyes narrowed at those words. "Tsk,"
"You just barely managed to pass, Senior Ceeran," Rui announced as he gave the man a smile.
Rui had been grilling them on their fundamentals very hard. He put an immense amount of pressure on them, and despite his instinctual fear towards both of them, he suppressed it and made sure to never let them off easy.
He couldn't give them an easy fun and joyful education when it came to what mattered, unfortunately. He had to impart an education intensity that matched high-intensity exam-prepping coaching classes.
What they were aiming to crack was much harder than any exam Rui planned to give.
Of course, when it came to the qualitative theoretical classes, he was a lot more patient, understanding needed to be nurtured, it could not be forced.
His own training was not easier than theirs.
The sustained underwater-sounding training drained his stamina at a rate that was scarcely believable. He was exhausted and his throat was sore to the point where he had trouble talking. If not for the healing and stamina potions he would have been extremely tired.
Yet as the weeks passed, he made improvements. He grew less tired from that particular exercise as he learned to execute it more efficiently and lower his heart rate and body temperature, among other things that allowed him to last much longer than his first time. He grew increasingly better and better as his diaphragm strengthened, and his larynx toughened.
Until finally, the day came when he could begin with the training of executing the technique.
"You have come far very fast," Kt'obila remarked with a surprised expression. "As expected of a Martial Artist as strong as yourself."
Rui smiled, without replying.
The truth was that he would have had to take at least twice as much time to master those techniques if he didn't have healing and rejuvenation potions. Thankfully, it helped to keep up his facade.
"Now that you have come this far, you simply need to take one more step," Kt'obila said as he got up, turning to face another direction.
He deeply inhaled, before opening his mouth ever so slightly.
The attack soared forward at a tremendous speed, far faster than his own Sonic Bullets did, before destroying a boulder the size of a building to smithereens in the distance.
"You need to leverage the strength that your breathing force and voice have gained," He explained. "Use all your power to force all that power into a small space in your mouth, and give it only the smallest opening to escape from your mouth while expelling it spontaneously and instantaneously."
Rui got up, inhaling deeply before attempting the technique with the instructions that Kt'obila had come up with. He pushed his diaphragm to the absolute limit, minutely opening his mouth before spitting out an extremely potent Sonic Bullet, that was much smaller and denser than any Sonic Bullet that he had ever released.
('It hasn't surpassed the atmospheric pressure to the degree that is needed to surpass the speed of sound,') Rui sighed.
"It's not bad," Kt'obila nodded. "Rather it's surprising that you're this good already. I have no doubt that you will master it soon enough."
"Well, I'll have to keep training to get there," Rui sighed.
Within three months after he originally began training, he had gotten hang of the Mighty Roar Flash Blast technique. He simply needed to make small, but enough progress every week, and eventually, he reached the stage where he could launch supersonic sound projectiles with tremendous pressure and energy density.
However, to Rui, this was just the beginning. The first step in his mind.
This technique was not the end goal. It was simply one of the ingredients that was necessary for his goal. It was simply one of the building blocks for his new technique. The fact that it helped the existing ODA system was also just a bonus at best.
He wanted to create a power accumulative technique that allowed him to surpass his long-range power limits.
('Once I create this technique, my long-range formidability will likely reach on par with that of my close-range formidability.') Rui noted.
He was never under the illusion that the Pathfinder technique alone could make his long-range prowess on par with his close-quarters combat. Yes, the technique was evaluated to be grade ten, but that did not instantly mean that his long-range combat would be on par with his short-range combat.
Pathfinder was best for assassinations. It still worked well in head-on combat but to a lesser degree. Compared to short-range where he had numerous techniques that were largely short-range, he had to admit that there was no way that he would be able to overcome those advantages with Pathfinder alone.
('But with this new technique…') Rui's eyes narrowed. He would become a genuinely well-rounded Martial Artist as far as range went. He would be effective at short-range, mid-range, and long-range.
"Time to set out on a new training phase!" He grinned. Now that he was free from Kt'obila's training, he could dedicate all that time towards the development of his own technique.