If the intel was correct.
The strength gap between Upper Ranks and Lower Ranks among the demons was practically a generational chasm.
His cheap master could manage to conquer a portion of the Lower Ranks.
Then the Hashira, who were stronger than him, naturally had an even easier time of it.
And the Upper Ranks...
Let alone defeating them, whether they could even survive an encounter was a rather difficult matter for many Hashira.
The strength ranking was clear: Upper Rank >> Hashira > Lower Rank ≈ Kazami Kōgi > himself.
He guessed that the late-game boss monsters were basically these things without a doubt.
However... since the enemy forces were so fierce.
Why was the Demon Slayer Corps still running some high-attrition bloody elimination tournament for recruitment?
Shouldn't they raise the entry rate to cultivate more talented swordsmen this way?
As for the Hashira, if they faced an Upper Rank alone, they wouldn't be able to defeat the opponent even by exhausting all their strength.
What about if two Hashira joined forces?
What if three or four Hashira coordinated in battle?
As long as the base of Demon Slayer Corps swordsmen was large enough, the probability of Hashira being born would naturally increase.
If the number of Hashira increased and they operated in squad formations, wouldn't survival rates increase drastically?
Facing demons that devoured humanity, were they really going to talk about solo jianghu rules?
Swarming them was enough.
After all, these Upper Rank demons only numbered six in total.
If not for Master Kazami's repeated assurances that Oyakata-sama Kagaya Ubuyashiki was a truly benevolent person, Xia Xi would almost have taken him for a deeply hidden schemer.
The kind of grey figure lurking behind the scenes, coldly manipulating the chess game.
Perhaps the topic had grown too heavy, and Kazami Kōgi intended to end the conversation here.
"Kurumaji, you should get a good rest these days. After a few days, when the uniform and Nichirin Blade are delivered, you'll have to fulfill the duties of a demon-slaying swordsman."
"Well... if your customized weapon takes a while, you'll probably just have to use an ordinary Nichirin Blade first."
"Don't push yourself too hard these past couple of days."
"We'll spar together and then prepare for missions."
With that, he cleared away the bowls and chopsticks in front of him and prepared to leave.
Yet Xia Xi stopped him: "There's one more matter, Kazami-san."
Then he inquired of Kazami in a roundabout way about the problems he had encountered while diligently practicing his Breathing Style.
His compatibility with the Wind Breathing Style wasn't very high.
It was a mere 65%.
This meant that for every three achievement points invested, one was wasted.
Extending from this problem.
Xia Xi even suspected that his speed in practicing the Breathing Style, and even the sword forms he executed, were likewise restricted by this compatibility.
If he practiced a Breathing Style with higher compatibility...
Under the same stats and skill levels, would his strength rise to yet another level?
If the compatibility were even higher, reaching 100%...
Even if no numerical values changed, it would very likely bring about an all-around, massive boost exceeding 50%.
Facing Xia Xi's inquiry, Kazami Kōgi did not blame him for aiming too high.
Instead, he earnestly explained it to him.
Although Breathing Styles had many schools like Wind, Thunder, Flame, Water, and Stone, they were essentially the same technique.
Namely, reinforcing bodily functions to the extreme through specific breathing rhythms and methods.
It wasn't special energy, nor was it a demon's Blood Demon Art.
Precisely because it was a technique, it naturally produced various subtle differences and adaptations due to the practitioners' respective physical conditions and structural traits.
This influence could be positive or negative.
For instance, someone with a tall build and thick bones.
Compared to the instantaneous burst-oriented Thunder Breathing Style, they were often much better suited for the fierce and direct Flame Breathing Style or the steady and heavy Stone Breathing Style.
Some people, though talented, had insufficient cardiopulmonary capacity.
Then, compared to Breathing Styles demanding more of the body, the Wind and Water Breathing Styles, which placed relatively gentle loads on the body, might be wiser choices.
To get into the details.
Even reaction speed and personality might subtly affect one's affinity for a Breathing Style.
Those with insufficient neural reactions would experience a distinct sense of stiffness when practicing the sword forms paired with the Thunder Breathing Style.
Boisterous people who were always straightforward would find it very difficult to bring out the flowing and shifting feel of the Water Breathing Style.
Of course, these differences usually didn't create a chasm of difference.
Because they fundamentally originated from the basic methods derived from ancient Breathing Styles.
The differences amounted to no more than some focusing more on strengthening cardiopulmonary bursts, some strengthening endurance and force generation, and some strengthening joints and specific parts.
The only slightly special one was the Water Breathing Style.
It was the one with the most lenient physical requirements for practitioners and the easiest to get into, which was why there were the most Water Breathing swordsmen in the Demon Slayer Corps.
If even the Water Breathing Style, with its strongest adaptability, felt difficult to master.
Then practicing the other four more demanding Breathing Styles would probably prove hard to enter.
"Hm? The thresholds for the Five Great Breathing Styles aren't the same?"
Xia Xi asked Kazami with a studious spirit: "Water Breathing is actually the easiest to get into?"
The old man gave an answer based on his own experience.
Nothing else; a rough answer could be obtained from the number of people practicing each Breathing Style within the Demon Slayer Corps.
Stone Breathing was the hardest category to master, placing the highest demands on physical fitness.
Thunder Breathing was equally difficult, but compared to physical fitness, it tested the learner's neural reaction speed and leg muscle groups even more.
Wind Breathing and Flame Breathing were more or less the same, except the former emphasized cardiopulmonary capacity and balance more.
While the latter tested limb bursts and strength more.
As for Water Breathing, although its threshold was the lowest, its core lay in neural reaction and coordination abilities.
The vast majority of demon slayer swordsmen also trained within these five basic schools.
Compared to choosing a Breathing Style that suited oneself-a problem that only needed to be considered at a certain level-they were more concerned with how to train their bodies to be stronger and how to survive in the hands of demons.
Hearing this, Xia Xi nodded in agreement.
The vast majority of players prioritized maxing out their levels first, and only whale high-rollers and pro gamers would build their skill pools and card decks right at the start.
Subsequently, he raised a tricky question.
"Then, what if none of the five Breathing Styles are very suitable?"
If the five basic schools targeted five common types of swordsman physiques.
Then there would always be some swordsmen with good talent but special physiques whose compatibility with all five types was likely very low.
Kazami didn't deny it.
The reason the Five Great Breathing Styles were called basic Breathing Styles was because over hundreds of years in the Demon Slayer Corps, there had emerged more than one entity who used other derivative Breathing Styles.
Whether gifted with rare talent or possessing a special bodily physique.
Based on the core of a certain basic Breathing Style, they adjusted or modified it.
Thus creating a derivative Breathing Style different from the basic methods.
It wasn't necessarily stronger.
But it was definitely more suited to the individual himself.
And those capable of creating their own Breathing Styles and leaving behind a certain reputation were at least senior swordsmen of the Demon Slayer Corps, or even beings approaching the Hashira.
However, come to think of it.
The Five Great Breathing Styles might also have been derivative methods developed in ancient times by referencing a Breathing Style with even higher demands on physical fitness.
Therefore...
Xia Xi drew a conclusion.
[Weapon] [Physical Fitness] [Technique] [Sword Move] [Breathing Style Type] [Breathing Style Level] [Breathing Style Compatibility]
Each one was an independent multiplier area during his battles that affected how much final damage could be dealt to demons.
To clear the game, one didn't have to reach the pinnacle in every single aspect, but there definitely couldn't be any obvious shortcomings.
Thus thought Xia Xi, who had carefully finished reading the plot this time.
"Sir, how can one develop their own Breathing Style?"
Kazami: "How would this old man know? This old man doesn't practice a derivative Breathing Style."
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