The goal of third-stage training was to normalize Total Concentration Breathing as much as possible.
The vast majority of people, although able to skillfully master Total Concentration Breathing, would find their stamina depleted after just one strike, causing their breathing rhythm to fall into chaos.
Masters of breathing techniques, even when using Total Concentration Breathing multiple times, wouldn't let their breathing rhythm become disordered.
Upon completing the third stage came the fourth stage—also the stage with the greatest physical enhancement.
Total Concentration: Constant.
The highest realm of breathing techniques. Those who reached this realm would be granted the title of Pillar.
Maintaining Total Concentration Breathing at all times, their physical capabilities far exceeded ordinary people.
And Xia Mi, as one of the school's top students, publicly displayed abilities at the third stage of breathing techniques.
But in reality, she had long since reached the fourth stage.
It had to be said, this miraculous breathing technique did indeed have impressive effects.
Even for someone like her—a Dragon King—it was the same.
It could push the physical capabilities of her dragon body even further.
She had awakened from a thousand-year slumber and infiltrated this completely different world.
Like a child, she came to understand this world and absorbed its knowledge.
This strange, unknown everything excited her.
Even if going higher carried the risk of exposure, she had to try.
The higher-level cultivation systems of this world might completely rewrite the fate of her and her brother.
"Almost there."
"Almost there."
Lin Chen breathed heavily, beads of sweat sliding down his forehead.
His breathing rhythm seemed chaotic, but he himself knew very clearly—
It wasn't chaotic.
On the contrary, his body was more active than ever. He even had the illusion that he could feel his blood flowing.
[Breathing Technique: Water Breathing LV2 (1/20)]
Finally.
A number on the Martial Arts Panel in front of him jumped, triggering more numbers to change.
It also triggered Lin Chen's heart to beat violently.
Inhale.
A forceful breath.
A large mass of air filled Lin Chen's chest cavity like solid fuel.
Raging blood burned within his body.
Driving his blood to flow rapidly, then power surged through his entire body along with the blood.
Every muscle fiber at this moment burst forth with power far exceeding its normal state.
The blood's high temperature burning within his body spread to his hands continuously until it spread to the wooden sword.
In an instant, they transformed into water-like slashing strikes.
"Total Concentration Breathing."
"Water Breathing: Second Form: Water Wheel."
Lin Chen's body vanished from Natsuki Subaru's sight in an instant.
Then appeared above his head.
Lin Chen's body stretched out, twisting in midair while holding his sword, unleashing a circular slashing strike.
Crack.
Under Natsuki Subaru's disbelieving gaze, the front section of the wooden sword in his hands shattered.
The wooden sword fell. He looked at his own hands.
His palms were trembling.
Thud.
Lin Chen fell onto the wooden floor in a rather ungraceful posture, gasping for breath heavily.
The explosive power of Total Concentration Breathing was extremely astonishing, but without skillful mastery, it could easily lead to over-exertion, resulting in oxygen deprivation and loss of strength.
That was exactly how Lin Chen felt right now.
His breathing was rapid, his lungs like a bellows, his vision darkening.
"Very good, very good."
The swordsmanship instructor had originally been in another corner of the classroom.
In the blink of an eye, he had already arrived before Lin Chen.
"Adjust your breathing rhythm."
The swordsmanship instructor placed his hand on Lin Chen's chest, moving it rhythmically to help him adjust his breathing.
This was quite effective—Lin Chen quickly recovered.
However, his body still felt somewhat weak.
"This is normal. Everyone experiences this the first time they use Total Concentration Breathing."
The swordsmanship instructor said with a smile.
"Remember the breathing sensation from just now—that's true Total Concentration Breathing."
Beginners who had learned breathing techniques would also take large breaths and momentarily enhance their bodies.
But that wasn't Total Concentration Breathing—the effects were vastly different.
The explosive power generated by true Total Concentration Breathing was extremely astonishing.
Just like Lin Chen—able to instantly use a wooden sword to cut through another solid wooden sword.
The other students around them heard the swordsmanship instructor's words.
Quite a few people looked at Lin Chen with envious gazes.
Being able to use true Total Concentration Breathing once basically meant stepping into the second stage of breathing techniques.
More than half of the entire swordsmanship classroom was stuck at this bottleneck.
There weren't many who had truly reached the second stage of breathing techniques.
Of course, people like Xia Mi were exceptions—her talent was at a level where even the principal would cherish her.
"That's great, Lin Chen."
Subaru's eyes dimmed for a moment, but he quickly adjusted and said to Lin Chen with a smile.
"Just lucky. You'll get there soon too, Subaru."
Lin Chen said while sitting on the ground.
Natsuki Subaru was indeed close—basically at LV1, just a bit of experience away from the second stage.
Of course, many people in the class were at this level.
As for when they'd break through, that really depended on talent.
Speaking of which, now that they were already in this kind of high-martial-arts world, Lin Chen didn't know if Natsuki Subaru would still undergo his transmigration.
The Re:Zero world was also a high-mystery world with several world-ending level powerhouses.
Though Subaru wouldn't get much protagonist privilege there.
After all, that world was also one filled with malice toward Natsuki Subaru.
Lin Chen's breakthrough was just a small episode.
Soon, people in the classroom resumed their individual combat sparring.
Perhaps because of Lin Chen's breakthrough, the students' enthusiasm was noticeably higher this time.
Lin Chen didn't continue sparring with Natsuki Subaru.
He just sat in a corner of the classroom, adjusting his breathing rhythm to recover his stamina.
He didn't need to do what the teacher said—recall his previous breathing rhythm to avoid forgetting it.
After all, one of the Martial Arts Panel's characteristics was "once proven, forever proven."
Since his breathing technique had already broken through to LV2, it wouldn't regress back.
What he needed to do was continue practicing the breathing technique constantly, gaining proficiency to pursue even higher improvements.
Of course, besides breathing techniques, swordsmanship also needed improvement.
Only by combining the two could he elevate his combat power even higher.
After recovering a bit of stamina, Lin Chen didn't continue looking for someone to spar with.
Instead, he took his wooden sword and began practicing breathing technique swordsmanship in place.
In the Demon Slayer world, breathing techniques and their corresponding swordsmanship were matched sets.
The earliest breathing techniques—like the five basic breathing styles—were Yoriichi's modifications based on the swordsmanship the original Pillars excelled at.
Different schools of swordsmanship required different muscles for power generation, and different power generation techniques, so the corresponding breathing techniques would enhance specific characteristics.
Therefore, breathing techniques plus swordsmanship formed the complete Demon Slayer system—of course, this was the human combat system.
Combining the two could produce an effect where one plus one was greater than two.
Lin Chen was currently cultivating Water Breathing.
According to his predecessor's memories, the school didn't have Sun Breathing either.
It probably wasn't because his level was too low to qualify, but rather that it simply didn't exist.
After all, in the Demon Slayer world, even within the Demon Slayer Corps, Sun Breathing had been lost between generations.
In the entire Demon Slayer world, only the protagonist Tanjiro's family had inherited Sun Breathing.
They didn't even know that what they had inherited was Sun Breathing.
Without God's perspective and unfamiliarity with the plot, it would be impossible to find the Sun Breathing inheritance.