After an unknown period of time, the commotion inside the training ground finally subsided.
"Alright, let's take a break for now."
Riezel, seeing many members of the Demon Slayer Corps gathered in the training ground, decided to sheathe his sword after some thought, and addressed the Hashira.
""Hahh... Hahh... Hahh...""
All the Hashira had no energy left to respond, one after another collapsing to the ground, desperately gasping for air.
"Dammit!"
Sanemi, panting heavily, wore a face full of frustration.
"Tch, couldn't even land a hit today..."
Obanai clicked his tongue.
Mitsuri felt like she was about to pass out, so she could only sit on the ground like a duck, struggling to speak.
"As expected of Young Tsugikuni!"
Even Kyoujurou, usually full of energy, couldn't get up.
"Namu Amida Butsu..."
Gyoumei stopped shedding tears, his whole body filthy as he recited Buddhist chants.
"Really, he's just too flamboyant, that guy..."
Tengen observed that Riezel's demeanor seemed different from before.
"...A monster."
Muichirou lay on the ground without regard for his image, quietly uttering an evaluation.
"..."
Giyuu didn't feel like speaking, silently staring at the sky, lost in thought.
"If only he had been born a little earlier..."
Shinobu sighed as she looked at Riezel.
However, her remark was met with silence from the Hashira.
After all, they naturally understood what she meant by that.
"Indeed..." Kyoujurou said sincerely. "If Young Tsugikuni had been born a bit earlier, maybe there wouldn't have been so many tragedies... I wonder, is Kibutsuji Muzan stronger than Young Tsugikuni?"
In the past, the Hashira would never have simply admitted to such a statement.
However, now, they no longer thought that way.
After all, for a whole week, they attacked Riezel countless times, yet they couldn't even touch the hem of his clothes, being knocked down time and time again.
One must know that this was nine versus one!
Nine Hashira were attacking a single person together, yet they couldn't even touch his clothes.
Who would have believed it before?
Not to mention, except for Gyoumei, all of them were fighting while using the Demon Slayer Mark.
Gyoumei, due to his old age, which posed a risk of immediate death upon its use, had Riezel help him get rid of the Demon Slayer Mark after he had successfully awakened it previously. As a result, during these days of fighting, he had been fighting without using it.
However, since Gyoumei was already the strongest in the Demon Slayer Corps, even without the Demon Slayer Mark, he wouldn't be weaker than the other Hashira who used it.
With nine Hashira like this, even if they couldn't defeat Muzan after ganging up on him, they should at least land a hit, right?
At least, this was what all the Hashira thought, until Riezel kept them from even touching him, continuously knocking them down for seven days straight.
In their eyes, if Riezel's terrifying strength was below Muzan's, then Muzan wasn't a demon anymore but a god.
"Don't get ahead of yourselves."
Riezel stepped forward and denied it.
"Tsugikuni Yoriichi from the Sengoku period was also a swordsman much stronger than Kibutsuji Muzan, but he still couldn't kill him, allowing him to escape."
His point was that being able to win was one thing, but being able to kill was another.
"Even I, facing Kibutsuji Muzan, who can split his body into countless fragments to escape, wouldn't dare say I can absolutely stop him from getting away. It's best not to cling too tightly to your delusions."
After hearing Riezel's words, all the Hashira became energized.
"Head Instructor, how strong do you think he is?"
Shinobu asked a question that everyone was concerned about.
They wanted to know if, at present, they had any chance against Muzan.
However, reality was still cruel.
"Unfortunately, even if you awaken three abilities and can defeat an Upper Rank on your own, it's still unknown whether you can defeat him even when fighting together."
Riezel honestly expressed his opinion.
He had a rough estimate of Muzan's strength, but this estimate was mainly based on the original work.
In the original work, as Upper One, Kokushibou's strength far exceeded that of ordinary Upper Ranks. He could single-handedly confront Gyoumei and Muichirou, both of whom had the Demon Slayer Mark and the Transparent World, along with Sanemi, who used only the Demon Slayer Mark.
Yet, despite the combined efforts of the three Hashira, they only managed to defeat him after one of them was killed in the process.
Kokushibou, conservatively estimated, should have a strength equivalent to Level 5.
Meanwhile, even while under the effects of Tamayo's drug, Muzan still could fight on his own against Tanjirou, Gyoumei, Sanemi, Giyuu, Obanai, and Mitsuri, a total of six people.
Even though these six people either used the Demon Slayer Mark, the Bright Red Nichirin Sword, or the Transparent World, Muzan could still single-handedly suppress them, forcing them to delay until daylight.
Just this performance alone was enough to prove that Muzan was much stronger than Kokushibou.
However, what made it worse was that this Muzan was not even at his prime.
Firstly, because centuries ago Muzan was nearly killed by Yoriichi, the wound left behind at that time hadn't fully healed even now, weakening his strength to a certain extent.
Secondly, Tamayo injected Muzan with a complex drug containing four deadly effects.
The first effect turned his demon body into a human body.
The second accelerated his aging.
The third prevented his body from splitting and escaping.
The fourth disrupted his cells after the first three had taken effect.
In the final battle, Muzan managed to neutralize the effect that turned him human, but the other three were still active.
In a situation like this, his strength was certainly halved.
Even so, Muzan could still single-handedly hold his own against the protagonist and five Hashira, showing that his strength in his prime would have been even more formidable.
From this, it was clear that Muzan, despite his weakened state, could still outperform Kokushibou, who was at Level 5.
In other words, Muzan might not have been far from Level 6 in his prime.
'Now that I think about it this way, Tsugikuni Yoriichi's strength seems terrifying...' Riezel pondered inwardly.
Muzan, possibly at Level 6, almost slain by Yoriichi?
What level was Yoriichi then?
He could only say that Yoriichi truly lived up to being the strongest character in the world of Demon Slayer. Not only was he born with the Demon Slayer Mark, but he was also the creator of the breathing style and learned the principles of the Transparent World from childhood—a true anomaly.
If Yoriichi were still alive, and if, like Riezel, could receive a god's blessing and fully unlock his potential, he would undoubtedly be a monstrous figure capable of pushing his limits and raising his basic abilities to SSS.
However—
'I'm not weaker than Tsugikuni Yoriichi now...' Riezel affirmed inwardly.
In his current state, when adopting a strong attack mode, his strength was already equivalent to middle Level 7, perhaps even surpassing Yoriichi in his prime.
If Yoriichi could defeat Muzan in his prime in an instant, there was no reason Riezel couldn't do the same. Even if Muzan were really at Level 6, Riezel could still easily defeat him even before learning Sun Breathing, let alone now.
Even with the Demon Slayer Mark, the Transparent World, and the Bright Red Nichirin Sword, which inflicted massive damage on demons, the strength of a single Hashira at best reached the limit of Level 4.
Even Gyoumei, who was the strongest in the Demon Slayer Corps, couldn't reach Level 5 even after using the Demon Slayer Mark and the Transparent World. At most, he could only be considered to have stepped partially into it.
If Muzan were in the weakened state seen in the later parts of the original work's main story, the nine Hashira might have a chance of successfully defeating him.
However, if Muzan were truly at Level 6, could the nine Hashira, who were not even at Level 5, really succeed in taking him down?
It was a big question mark.
Understanding Riezel's point, every Hashira furrowed their brows.
"Is Kibutsuji Muzan really that strong?"
Tengen wondered aloud, to which Riezel responded with a simple affirmation.
"After living for a thousand years, even a pig can turn into a demon, let alone a ruthless demon like him. Don't forget that demons grow stronger the more they consume humans. As the progenitor of demons, who else in this world has eaten as many humans as him?"
It could be said that under normal circumstances, no one in this world could surpass Muzan in combat power.
Yoriichi was simply an exception, a miracle.
As all the Hashira looked at him solemnly, Riezel continued his words.
"However, I don't support risking your lives by going after Kibutsuji Muzan—it's unnecessary."
"Your real opponents are the Upper Ranks, many of whom have a history with you."
"That's who you should be targeting."
"As for Kibutsuji Muzan..."
Riezel turned his body away, ready to leave.
"He's already mine."
With these words, Riezel left the training ground, leaving the Hashira deep in thought, staring at his retreating figure.
===
"M-Mr. Tsugikuni!"
Meanwhile, as Riezel was about to leave the training ground and return to his house, a voice called out to him.
"Hmm?"
Upon hearing this familiar voice, Riezel halted his steps, turned around, and glanced behind him.
Over there, someone was running toward him at a brisk pace.
"Tanjirou?"
Yes.
It was none other than the protagonist, Kamado Tanjirou.