The Martial Unity

The Heavenly Convergence technique applied tremendous pressure on the target. Gay-Lussac's Law required immense pressure for immense heat; thus, it was the perfect technique to use.

Rui was immensely satisfied with the theoretical framework that he had created for the Muspelheim domain. The domain involved three forms of heating at the moment: 1) passive convection, which would happen naturally after exhaling super-heated breath; 2) active pressure-heating that required active effort and conscious control; and 3) friction-heating through earth-bending if he was in contact with the ground.

With these two elements, Rui was quite confident that the theoretical framework of the Muspelheim domain technique was complete. While he would have loved to add a fourth element to the technique, it was beyond his capacity to handle at the moment.

Three solid methods of heating was more than enough, especially when he needed to exert force to isolate his domain from the outside world to ensure that heat didn't leak. On top of that, adding a fourth element would make the technique extra-difficult for passive mastery which was also main objective of the Muspelheim technique.

"And with that, I have completed the theoretical framework and blueprint of the Muspelheim technique."

Now, he just needed to flesh out the training regime of the technique, keeping in mind that he sought to reach passive mastery.

"Thankfully, friction-heating is a lot easier to reach passive mastery for than normal domains."

Every time someone walked, they generated heat using the same friction that they propelled themselves forward. Every ounce of force that they applied on the ground would end up being used for friction. Every time he maneuvered, he could simultaneously use that to create heat in the bedrock of the land beneath his feet.

"Wait, friction isn't the only way I can heat the ground beneath my feet." Rui realized as an epiphany flashed in his mind. "I can also use Flux Earther!"

Flux Earther absorbed the opponent's energy and harmlessly redirected it to the lands beneath his feat. That was the purpose of this original technique that Rui had created. However, as he belatedly realized, this wasn't its only application.

"I can use my opponent's power to heat my domain."

He could use his opponent's power to fuel his domain and maintain it throughout the entire fight. Instead of harmlessly projecting all that power down the drain, he could use it to heat the land beneath his feet using acoustic conduction.

Acoustic conduction was the same principle that was used for the Sonic Singularity technique. Sound converged into a single target through the air, causing the vectors to cancel out and the order to crumble, becoming scalar chaotic heat within the target.

If he applied acoustic conduction through the Flux Earther to the land beneath his feet, he could heat it up extremely quickly, free of cost.

He could use his opponent's energy to cook them!

"It's genius!" He grinned, quickly revising the theoretical framework of Project Muspelheim, adding a fourth element of heating to the project.

On top of that, it would mean that Muspelheim would grow stronger and stronger the more Rui adapted to his opponents with his systems of thought. Once he reached a stage where the predictive and SOUL models were established, Flux Earther would grow vastly more powerful, which would mean that the Muspelheim domain would grow vastly more powerful.

Already, Rui could not imagine how powerful this domain would grow to become when he completed it.

It had the potential to become the most powerful domain he had ever created. If he ever ran into a creature whose antithetical environment, according to the enlightenment of the Tree of Life, was a heat domain, then they were so dead that it made Rui laugh giddily.

"Damn, I shouldn't have killed that dragon!" He cursed himself. "I missed the opportunity of watching it suffer in a domain antithetical to it when I complete Project Muspelheim."

Project Muspelheim truly excited Rui. He immediately rushed to flesh out its training regime now that he had updated it.

"I need to master generating heat through friction with regular maneuvering." Rui thoughtfully considered. "Thankfully, I know all my combat patterns. Thus, I can tailor a training regime specifically to my patterns."

This was where Rui's Martial Art gave him an edge over all other Martial Art. His own systems of thought allowed him to create absolutely perfect training regimes for himself while others followed more generalized methods that were not optimized for him.

Furthermore, with the recent revelation that domains could help him condition his own body, he had freed himself from needing to rely on anybody but himself, which allowed him to customize his training even more.

It was possible that he might finish his current training arc in merely two years. Thankfully, the burden of time had been removed from him the moment he stepped into the Mellow Manifold.

"Master generating friction with my maneuvering patterns, Practice internal breathing pressure-heating, Master applying Heavenly Convergence to an entire domain rather than a target. Master applying local Sonic Singularities with Flux Earther."

The latter was definitely the hardest but also the most powerful since it didn't require using his own power but instead absorbed his opponent's power and used it against them. However, he had already begun fleshing out the specifics of how he was going to go about mastering these four elements of heating.

"Alright, now for Project Niflheim."

One would think that being so engrossed in heat generation would mean that he was less excited about a cooling domain, but alas, that was not true.

"A lot of the insights I gained from working on Project Muspelheim can be used to improve Project Niflheim."

Hot and cold were two sides of the same coin. The inverse of heating was cooling. Many of the principles that Rui had used for heating, when inversed, could be used to get rid of heat. In fact, just thinking about how he could further reduce his time by making efficient use of concepts from Muspelheim made him even more excited.

"This might be one of the most productive training arcs of my entire life."

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