After the two got used to this training intensity, Urokodaki Sakonji officially began to teach them the Breathing Technique.
The Breathing Technique was a skill developed by Yoriichi Tsugikuni, created to allow ordinary humans to fight demons with their flesh and blood.
It primarily strengthens cardiopulmonary function through breathing, allowing the body's blood to absorb a large amount of oxygen in a very short time, thereby greatly enhancing one's physical abilities, giving humans the physical strength to contend with demons.
Different Breathing Techniques have different characteristics, but continuously maintaining this Breathing Technique can place a very severe burden on the body.
This is also why Urokodaki Sakonji first spent a great deal of time improving their physical fitness before beginning to teach them the Breathing Technique.
When one can operate the Breathing Technique with full concentration even while sleeping, one has entered a higher realm of the Breathing Technique—'Total Concentration: Constant.'
And only by thoroughly mastering 'Total Concentration: Constant' is the minimum requirement to approach the strength of a Hashira.
Urokodaki Sakonji began to guide them step by step in changing their breathing methods.
"Relax your upper body, keep your lower body stable and still. Good, breathe!"
Luo En could easily perceive the difference in breathing methods and adjusted quickly, but Tanjiro struggled. He tried various breathing patterns but couldn't grasp the key, making Teacher Urokodaki so angry that he hit his stomach several times.
Although Luo En could adjust, he didn't feel any increase in strength yet. It seemed that simply doing this wasn't enough.
For Water Breathing, Urokodaki Sakonji still took them to the bottom of a waterfall, letting them experience the flow of water and merge with its essence.
Boom—!
The surging waterfall was like a water dragon, roaring as it crashed onto Luo En's shoulders and back. Every drop of water seemed to possess immense power, threatening to shatter his bones.
He gritted his teeth, his legs deeply submerged in the icy stream, maintaining his sword-swinging posture. The muscles in his arms had long surpassed soreness, entering a burning numbness!
A year had passed.
Since stepping onto Mount Sagiri, day after day of extreme training had polished him into a stubborn rock.
Urokodaki Sakonji had taught them all the knowledge he could impart; the rest was up to them to master through practice.
The old man took Tanjiro to a boulder as tall as a man and told him that if he could cleave it, he would be allowed to participate in the Final Selection.
Despite thinking it impossible, Tanjiro picked up his sword and began his attempts.
Urokodaki then turned to Luo En, telling him to take his sword and practice under the waterfall.
After this year, Tanjiro had already grasped the basics of Water Breathing under Teacher Urokodaki's angry shouts and strikes. Luo En, however, remained stuck outside the door.
Luo En had mastered various aspects well, but he was lacking in the Breathing Technique, which was precisely the most crucial part.
His perception allowed him to easily understand the principle of the Breathing Technique changing the heart and lungs and stimulating blood, but he couldn't do it.
Whenever he tried to guide that qi, the magic power circulating within him would produce silent resistance, like loose sand. No matter how the torrent of breath washed over it, it could not be condensed.
This power from another world became his greatest shackles.
The only thing he could feel was that with each extreme breath and sword swing, the dormant magical dust deep within his body seemed to have an extremely, extremely faint, almost illusory... tremor?
There was a vague illusion that something was about to break free!
"Hoo... hoo..."
After another sword swing, Luo En finally couldn't hold on, staggering out of the waterfall's impact range, leaning on his sword and panting heavily.
Water droplets slid down his pale cheeks. He wiped his face and inadvertently glanced into the distance with his raised eyes.
Deep in the forest, on the giant rock that Tanjiro challenged day and night, a figure sat silently.
He wore a fox-patterned mask similar to Teacher Urokodaki's, had neat short hair, and a posture as straight as a pine tree.
He vaguely appeared to be non-physical, with a faint glow surrounding him, almost merging with the air.
A soul!
Luo En's breathing instantly stopped. He could "see"! He could clearly see that "existence" that should not be seen by the living!
Sabito... this name, and the story related to him, instantly surfaced in Luo En's mind.
During the Final Selection, Sabito, to protect others, killed all the demons on Fujikasane Mountain except the Hand Demon. Because of this, he encountered the Hand Demon, who had killed several of Urokodaki's disciples, and was ultimately killed by the Hand Demon.
Luo En knew that the souls of Sabito, Makomo, and other Urokodaki disciples had returned to Mount Sagiri, and he also knew that they would appear at this time to guide Tanjiro.
But Luo En didn't expect that he could also see them. This was his first time seeing and truly feeling the existence of a soul.
"This world... even death doesn't necessarily bring rest!"
Luo En looked up again in Sabito's direction. The figure seemed to notice Luo En's gaze, turning his head slightly. Through the mask, his eyes seemed to meet Luo En's for an instant.
No words were spoken, yet it was more profound than a thousand words.
A current ran from Luo En's spine to the top of his head. He took a sharp breath, refocusing his attention on himself.
If the Breathing Technique is a skill for guiding "water flow," then what is the magic power within my body? Is it a stubborn rock obstructing the flow, or... another undercurrent hidden beneath the riverbed?
He turned and walked back under the cold waterfall, closing his eyes.
This time, he no longer forced himself to imitate the rhythm of Water Breathing. Instead, he immersed his entire spirit within his body. He imagined himself as the ceaselessly flowing stream, and those magical dust particles as the sand at the bottom of the water.
"Hoo—"
As he inhaled, he guided an invisible momentum, gently swirling those dormant magical energies like a current.
"Suck—"
As he exhaled, he infused this "momentum" along with the magic into every muscle tremor, every swing of his blade!
This time, the feeling was completely different!
The incompatible magic power within his body, for the first time, complied with his will. A peculiar energy, seemingly a fusion of intensely cold ice springs and his own magic, instantly flowed through his limbs and bones, dispelling all fatigue and bringing an unprecedented, bone-chilling clarity!
Just then, the training sword he held tightly in his hand suddenly felt unusual!
Buzz—!
The training sword in his hand emitted a clear, ringing hum.
A visible layer of light blue frost, like condensed moonlight, instantly spread from the hilt to the blade!
Crack!
A faint but crisp sound of freezing echoed.
The tip of the blade, where the light blue magical aura covered it, showed a layer of crystal-clear thin ice condensing and spreading visibly out of thin air!
It was no longer just a watery aura covering the blade, but it had genuinely changed the state of matter!
At the tip of the blade, a massive cold air gathered, and the moisture in the air was instantly frozen and shaped!
A three-inch long, crystal-clear ice blade, emanating a chilling cold, appeared out of thin air!
The "form" of Water Breathing and the "essence" of his magic finally merged into one at this moment, creating an anomaly.
Luo En also discovered that this anomaly not only endowed the blade with ice power but also completely changed the essence of his magic.
The previously dust-like, unaligned magic now seemed to be imbued with the spirituality of water and the chill of ice, possessing distinct "water" and "ice" characteristics!
This allowed him to use magic to condense ice blades and water blades for attacks, just like the demons of this world use Blood Demon Arts!