Inside the Mangekyo's spiritual world, Mifune looked at his own body and sighed.
He knew this was a spiritual realm; once he left, he would return to the body of a dying old man. But it didn't matter anymore. He was an old man, after all...
"Nagi, my brother," Mifune said with a sigh, "what happened to me was fated to be. You don't need to feel guilty. On the contrary, the battle with the Raikage allowed me to take the final step, to completely fuse the Breathing Style I just developed with my swordsmanship." Mifune's voice was filled with excitement.
"Mifune, my friend... I..."
"Don't speak yet. There isn't much time. I will demonstrate it for you now. As long as you remember it and pass this Breathing Style and swordsmanship down to the samurai of the Land of Iron, I will have no regrets in death."
"This is a fundamental Breathing Style that I have researched and improved. In the time we've spent together, I've noticed that the elemental Breathing Styles you possess may not be suitable for everyone. Even someone with a water affinity might not be a perfect match for the Water Breathing Style."
"Yes," Nagi nodded. Mifune's analysis was spot on. That was why the Hashira in the world of Demon Slayer had all developed their own Breathing Styles from the original ones. The Sound Hashira, Tengen Uzui, had a lightning affinity, yet he created his own Sound Breathing from Thunder Breathing instead of using it directly in combat. This was because, while their affinities were the same, it wasn't a perfect fit for him. And from Water Breathing, Shinobu Kocho and Obanai Iguro had developed Insect Breathing and Serpent Breathing. At their core, they both had a water affinity, but their compatibility wasn't one hundred percent.
Mifune, using his decades of experience as a sword saint and his observation of Nagi's various Breathing Styles, combined with the practical situation of the samurai in the ninja world, had developed a foundational Breathing Style. This style could be used by people of any affinity, and the entry barrier was low. What came after would depend on individual talent.
Just as the Sun Breathing could not be inherited by others, leading to the creation of the five elemental Breathing Styles for different people to inherit, Mifune had taken those simplified five styles and simplified them even further... Its power, of course, could not compare to the five main styles, and it was a far cry from the Sun and Moon Breathing Styles, but its advantage was its extremely low barrier to entry.
"This is as far as my demonstration goes..." Mifune sheathed his sword, filled with emotion. "To think that in my old age, I could still create such a magnificent sword art."
Mifune looked at Nagi and smiled. "Nagi, my brother, do you know? Although the samurai of the Land of Iron revere me as a sword saint, I know the truth of my own situation. I was just a man with a title, no real substance to my name. To be called a sword saint... it was the greatest joke under the heavens."
"But now, it's different. Once this Breathing Style is passed down, the strength of the Land of Iron's samurai will rise to a new level in the years to come. At the very least, they won't be suppressed by ninja as they were before. Heh, to be canonized as a saint after death... that's not bad at all."
"I'm sorry, Mifune," Nagi said apologetically. "If it weren't for me, you wouldn't have..."
Mifune waved his hand. "It's a small matter. I should be thanking you. You so generously displayed your Breathing Styles and swordsmanship, without a care in the world. I've stolen so much of your teachings, and you never minded. I'm the one who should feel guilty."
"Alright, send me out. It's a pity I won't be able to witness your battle with the Raikage. I imagine the fight between you two will be even more spectacular..."
Nagi nodded. He could have continued to pour his dojutsu power into the illusion to maintain it for a little longer, but all good things must come to an end.
"I look forward to the day you become the strongest swordsman in the world."
"Hahahaha..."
In the spiritual world, Mifune laughed heartily as he dissolved into a shower of light...
Returning to reality, Mifune had already stopped breathing. There was blood on the corner of his mouth, but his face wore a look of contentment. His hand was still gripping Nagi's tightly.
Mifune was dead.
Nagi sighed. There was no need to even close his eyes for him; he had already closed them himself.
Sigh...
"Are you done with your goodbyes? It's time to settle our accounts, Uchiha Nagi," the Fourth Raikage, A, said from the ground, his eyes blazing with fury.
Although it had felt like a long time in the spiritual world, only a moment had passed in reality. In that instant, A could have pursued and attacked, but for some reason, he had given them that moment to say their farewells. He could see that Nagi was using his Sharingan to say goodbye to Mifune in a world of genjutsu. Perhaps it was out of respect for that final, life-burning slash that had cut through his Lightning Armor, but he had not taken advantage of the situation. He had waited...
"Yes, we're done. What did you want to say, Fourth Raikage, A?" Nagi's Mangekyo was already open. A's speed was so incredible that even Sasuke, with his Mangekyo, could follow his movements but couldn't land an Amaterasu on him. Sasuke's body couldn't keep up with his rhythm at all, forced to rely on his Susanoo for passive defense.
"You stole the Hidden Cloud's Island Turtle, and you killed our ninja. It's time to settle this score." A's hair stood on end like a hedgehog's spines.
Nagi frowned. Stealing the Island Turtle was a fact, but he hadn't killed a single Hidden Cloud ninja... Could they have met with an accident on the way, killed by someone else?
But the Fourth Raikage wasn't listening to any explanations. A murderous aura filled the capital city of the Land of Iron. The samurai outside could feel the overwhelming killing intent and chakra. But no one was foolish enough to charge in. The Land of Iron was more like a confederation; Mifune was the nominal leader, but he didn't have a legion of Kage guards protecting him like the leaders of the five great nations. Many samurai had already sensed that something was wrong and were beginning to gather reinforcements, but they didn't know that their sword saint, Mifune, was already dead.
"You bastard!" the enraged Fourth Raikage, A, teleported in front of Nagi in a tenth of a second, throwing a punch. But it only hit an afterimage as the rooftop shattered.
Nagi, holding Mifune's body, placed it in a safe place to avoid it being destroyed in the battle, then teleported back to the battlefield with the Flying Thunder God Technique.
"Flying Thunder God: Second Step? Minato Namikaze used that trick to beat me and Killer Bee by half a step back in the day. But only by half a step. He couldn't do anything to us," the Fourth Raikage said with a smirk.
In that past battle, his defense with the Lightning Armor active was not something a single kunai could pierce. And even without the Lightning Chakra Mode, a kunai couldn't break through his physical body. Minato's most powerful jutsu was the Rasengan, which was completely ineffective against his Lightning Armor. And as for Killer Bee, even if he was in his human form, as long as he transformed into his Tailed Beast state, Minato couldn't hurt him either. The end result was that they couldn't catch or hit Minato, and Minato couldn't break their defense. So they just stared each other down... Fortunately, both sides were intelligent. After a few exchanges, they understood each other's strength and retreated without a pointless fight. Otherwise, while Minato couldn't have stopped them, he could have flown to their rear and slaughtered their ninja army.
"It's a pity he died so young and we couldn't have a second duel. But let me tell you, the Flying Thunder God Technique won't be enough to beat me." As soon as the words left his mouth, A had already transformed into a streak of blue lightning, hurtling towards Nagi.
How fast was lightning? The answer was, as fast as the Fourth Raikage, A. Before Nagi could even blink, he was right in front of him. Faced with this speed that was almost like teleportation, Nagi could only use the Flying Thunder God Technique once more.
One, two... there are three kunai on the field, plus two he's secretly marked for the Second Step. A had already memorized all the coordinates. The moment Nagi teleported to another location, he had already charged over. And before he left, he had stomped hard on one of the kunai, destroying it.
He's too fast... Nagi didn't dare to blink. In the instant it would take to do so, before his eyelid had even lifted, A could vanish from his sight. And letting him disappear from his field of vision was a terrifying prospect.
Dealing with a Kage-level powerhouse like the Fourth Raikage, who combined speed, strength, and defense, was extremely tricky. Many ninjutsu and Breathing Styles either couldn't hit him, couldn't break his defense, or lacked his raw power. But he couldn't just keep running. Nagi threw a kunai into the air...
The Fourth Raikage reappeared on a rooftop, and as he brought his fist down with a heavy blow, Nagi had already teleported into the sky, his hands beginning to form seals.
"Shuriken Shadow Clone Jutsu!"
Hmm? A was a little confused. Can that thing even hurt anyone?
Swoosh swoosh—
A single kunai multiplied into thousands, released in a storm of metal.
"Everyone, fall back!" A's guard, Darui, quickly retreated with his men. The metal storm was simply too vast.
Mifune's residence was already in ruins. Between the Raikage's brutish charges and Nagi's metal storm, it had been completely torn apart.
Nagi landed lightly on the ground, a scornful smile on his face. "Warm-up's over. Now we begin for real. This entire estate is covered in my Flying Thunder God kunai. Let's see how you deal with that."
He had already noticed A's little trick, destroying his markers to leave him without coordinates. Heh, too naive. Here's a few thousand for you. A few thousand shuriken shadow clones, with real Flying Thunder God kunai mixed in. Find them. Go ahead, I'd like to see you try. I made my Flying Thunder God kunai to look exactly like all the others, precisely so you couldn't single them out and destroy them.
"You bastard!" Feeling looked down upon, the enraged Raikage, A, was the first to attack.
"Lightning Release: Liger Bomb!"
The moment his punch landed, Nagi had already vanished. The ground was littered with kunai, so he easily teleported behind the Fourth Raikage.
"Thunder Breathing, First Form: Thunderclap and Flash, Thirty-Two Fold..."