Dream of the Sword Saint: Oneiric Kensei

The Plane of Euthymia. The mental landscape of the Narukami Ogosho, the Archon known as Beelzebul, or as everyone else knows her, Raiden Ei. She spent the past 500 years meditating in this inner plane, letting the Puppet Shogun rule over her people. Now, this inner world has been invaded by an Outlander, one strong enough and skilled enough to prove a challenge to the millenia old deity. The normally grainy landscape was dyed purple with Electro energy, with the red skies blotted by unnatural lightning storms. Storms that shot down yellow lightning known as 'The Lightning of Tomoe'. The Archon and the Sword Saint stared down each other with their full power, waiting for the other to make a move first, surrounded by the deafening sounds of thunder.

"RRRAAAAAAAHHH!" Isshin was the first to break the stare, rushing towards the Baleful Shadowlord while the Lightning of Tomoe struck him continuously, imbuing both the Black Mortal Blade and Gyoubu's Horn Spear with them.

"PURGE ALL OBSTACLES!" Ei responded in kind, unsheathing the massive blade and moving to meet the Sword Saint's strikes.

BOOM! BOOM! BOOM!

Each clash resulted in an explosion of yellow and purple energy. Every strike was followed by the deafening reverb of thunder. The blowback would've sent any normal combatants back hundreds of feet, but neither of these two were normal, as they continued clashing, the ground beneath them cracking at each impact.

"!" Isshin's opponent disappeared from sight, leaving him momentarily confused before she reappeared behind him, preparing to do a downwards slash. In response, Isshin jumped high in the air and gathered wind to his blade.

"PERISH!" Ei and Isshin slashed down their strikes, resulting in a violent storm of wind and Electro energy, but that didn't stop the Sword Saint as he followed up with a mad dash towards the Shogun, gathering wind to Gyoubu's Horned Spear, preparing to bring it down on the Electro Archon. "!"

Ei could only block with that massive sword, she wasn't expecting him to move that fast, especially with all the injuries the two have inflicted on one another. In fact now that she thought about it, the longer the fight went on, the more vicious and aggressive the man's attacks felt. And that smile he had on his face. "How can a mortal hold so much pow-" She didn't even have time to finish that thought before she was pushed back from the struggle. "Ghhkk!" Isshin wasted no time, and followed up with a relentless assault.

CLINK! CLINK! CLINK! CLANG! CLANG! CLANG!

Ei couldn't block all of the attacks in time, with some cutting her. While the damage was lessened in this form, it was still substantial enough that she knew that any more direct attacks could spell her end. The Sword Saint's brutal assault ended with a single gunshot.

BANG!

The Shogun managed to block the bullet, but it sent her a good distance away, yet she wasted no time, and proceeded to launch a shadow and numerous ranged slashes towards the Sword Saint.

"HAHA!" The shadow jumped out of the ground and attempted to smash the man, only for him to jump a considerable distance away from said hand. Not missing a beat, he dashed and weaved through the barrage of slashes while making his way towards the Shogun, pistol in hand.

BANG! BANG! BANG! BANG!

The Shogun brought up one of her hands to block the bullets while summoning another hand and shaped it like a fist before launching it at Isshin.

"GHHHK!" Isshin took the full brunt of the punch, sending him up in the air. Despite his chaotic movement, he charged the Black Mortal Blade, funneling black energy into the sword. The Baleful Shadowlord charged up the sword and dashed towards the human.

CLANG!

The two unsheathed their blades, discs and slashes of Electro and black energy clashing. Isshin, not wasting a second, parried off one of the slashes and attempted a diving Ichimonji strike to bisect the Shogun only for her to disappear.

"Now where did you go Raij- !" Isshin's sentence as he felt something slam into the ground, followed by several more slams.

"ETERNITY IS IN MY HANDS!" Several totems were embedded into the ground, and Ei reappeared, making the totems emit waves of Electro energy.

"! GHHRRRK!" Isshin took the full force of the waves, but he didn't let the pain stop him, stomping his foot on the ground. Fire erupted from the cracks, but that wasn't all, as he began to funnel wind into his blade.

"What is h-" The Shogun couldn't even finish that thought before she saw red.

"GRRRAAAAHHH!" Isshin swung in a circular motion, completely annihilating the totems, and leaving the area in an inferno. The Plane of Euthymia was now surrounded in a ring of fire. Ei's spectral arms were completely shredded as they took the full brunt of the blow, and just being in the area was suffocating due to the oxygen being burnt away. This had to end. Now. Ei teleported away to end this duel.

"LET'S END THIS RAIJIN!" Isshin raised the Black Mortal Blade into the air, funneling everything he could into it. The flames, the wind, the black energy, with the Lightning of Tomoe striking him an innumerable amount of times.

"WITNESS… THE FINAL CALAMITY!" A large portal opened up in the sky and a large arm and sword came out from the portal, preparing to slash at Isshin.

Three.

Two.

One.

Isshin brought down his blade as Ei swung her massive sword.

Time seemed to stay still in that moment. Not a single thing in the Plane of Euthymia was moving. Until…

Crack. Crack.

BOOM!

Everything exploded, the resulting clash caused shockwaves and a deafening reverb as the reality of Euthymia was literally shattering apart. The ground was charred, the Torii gates were completely annihilated, and the sky holding the black sun was literally shattered. And the two warriors? They laid on the ground. Slashed, burnt, and bleeding. Isshin's robe was completely torn apart, and his kabuto helmet laid in pieces on the floor. Ei reverted back to her original form, with her own attire tattered and charred.

"... Hnnn…" Isshin and Ei both were attempting to get up, attempting to balance themselves with the Black Mortal Blade and the Musou Isshin respectively.

"Haah… haah… haah… hehe… hnnnng… that hurt…" Isshin grabbed his side, recoiling from the pain, before resuming a battle stance.

"Haah… haah… I'm ending this… mortal…" Ei responded by resuming a battle stance. Both of them were worn out, out of energy, and out of moves. It was clear that their next move would be their last.

Isshin charged the Black Mortal Blade with its black energy, while Ei funneled all the Electro energy she could into the Musou Isshin. Seconds felt like minutes as the two prepared their final clash. It seemed that moment would never come until…

"!" The two dashed at each other.

CLANG!

The black energy clashed with the Electro energy, further destabilizing the mental landscape. The two were in the same position they began in, clashing with their blades attempting to overpower one another. For a few, split seconds, the two were at a deadlock. Neither could get the advantage over the other, it seemed that both would collapse before they'd be able to finish off the other.

"!" Isshin felt his fatigue finally catching up with him, and Ei took advantage of that split second of weakness and overpowered Isshin's blade, and delivered a clean slash through his torso.

"GHHHK!" Isshin let go of the Black Mortal Blade and Gyoubu's Spear before collapsing to his knees. It seemed that he'd fall to the floor, before stopping himself and delivering a warcry. "GAAAAAHHH!"

"Is he still alive?!" Ei prepared for Isshin to make a move, but to her surprise, he didn't move a muscle. In fact, he was just sitting here, as if he was waiting for her to execute him. "..." Ei proceeded to raise the Musou Isshin to give him what he wa-

"You can't kill me with that blade… Use mine."

"... I see." Ei reached down to the ground and grabbed the Black Mortal Blade, before asking the Sword Saint one final question. "Any final words?"

"... To think I'd be able to experience such a dream. This was the most fun I ever had. I have no regrets. Send me back to the afterlife."

"..." Ei complied with the man's request and brought the blade down on his neck.

Slash.

Isshin's corpse fell to the ground, with a smile on his face. The Sword Saint was now truly gone.

"... Farewell… Isshin Ashina…" Ei continued holding the Black Mortal Blade, still surrounded by the destroyed state of the Plane of Euthymia.

—-

"If this is a dream, somebody pinch me." The Raiden Shogun was bandaged by her familiar, the head Shrine Maiden of the Grand Narukami Shrine, the kitsune Lady Yae Miko.

"Miko, I can assure you. This is no dre- OW!" Ei promptly stopped sentence upon feeling her friend tighten the bandages.

"I was joking, Ei. Still… to think that someone could do this to you, and in the Plane of Euthymia no less." The priestess continued tending to her friend, before further inquiring about the situation. "And you said the one who did all this was a human?"

"As unbelievable as it sounds. Yes." Ei had a serious look on her face, one that almost made Yae think that the Puppet Shogun had taken over, before she continued to talk. "He was merely a man, yet had the strength and pride to face a god at full power… when was the last time such a mortal existed?"

"Hmmm, can't say. It was likely before my time."

"... Isshin Ashina…" Ei looked at the Black Mortal Blade currently displayed on the walls of the Tenshukaku, and for a brief second, had the smallest hint of a smile show up on her face, something which her familiar didn't miss.

"So you lock yourself away for 500 years, leaving poor old me all by myself, only to come out when an Outlander shows up on your doorstep. And then you go ahead and have a little tryst with another one? Truly, you wound me Ei." The kitsune struck a fainting pose while saying her words in mock hurt.

"Miko…"

"Hehe. Still, I can't remember when was the last time you were so fond of a duel, if ever for that matter." The familiar could tell, while the Shogun might not have outwardly appeared it, she too greatly enjoyed the encounter with the Sword Saint, to the point that the kitsune could tell that even now, her mind was still on the duel. "Now, what do we do with that?" Pointing towards the black katana on the wall.

"It can't be destroyed. And it would be too dangerous to be left out in the wilderness. It will stay in Tenshukaku until I and the Tenryou Commission figure out a safe place for it."

"Why not just throw it to the bottom of the ocean?"

"Miko, you sense the aura emanating from that blade as I do. If that blade were to accidentally come into contact with one of the leylines at the bottom of the sea, there could be disastrous consequences."

"Hmmm, fair enough I suppose." Yae stood up as she was finished bandaging her friend. "Well, if that's all, I believe I'm free to leave now? I have a meeting with my editorial staff in an hour."

"Thank you Miko."

"No need for thanks, I'll take my payment in Fried Tofu for the next year."

"Miko, you know I can't cook."

"Who said you'd be the one making it?"

"... Miko…"

"Haha, until next time Ei." The kitsune took her leave, leaving Ei by herself. She took one last look at the Black Mortal Blade before leaving the room.

A few minutes passed in the room after Ei left, when a shadowy figure emerges from beneath the ground and retrieves the blade before silently sneaking back in.

—-

The room was dark and devoid of light. The very air felt like it could freeze someone just by being in it. But none of that mattered to one of the residents, currently chained up and sealed by talismans. Who was this person? None other than the heretical samurai, Genichiro Ashina, currently detained in the lowest level of the Detention Center for the crimes he committed a few weeks back. Today was the same as the other days, complete isolation from everyone and everything, any normal person would've gone mad by now. But Genichiro was no normal person. No, he kept his mind focused through three thoughts, and three thoughts alone. Breaking out, burning this heinous land to the ground, and claiming the heads of the Tengu responsible for his capture and the Kitsune responsible for these talismans. Today should've been like any other day, when suddenly his thoughts were interrupted by a shadow figure emerging from the wall.

"Well, you certainly look like you've seen better days." This figure wasn't human, Genichiro could tell that much, just being near this… thing made his skin crawl. He felt this thing could have only been born in a realm cursed and abandoned by Buddha, little did he know how right he was. This creature was twisted and spat out from a place known as The Abyss, and it was known as an Abyss Herald. "Worry not human, I come bearing gifts." The Abyss Herald reached its hand into the shadow, and what he pulled out almost made Genichiro yell in surprise.

"!" There was no mistaking it, what that creature held was none other than the Black Mortal Blade. But how? How did it come to be in this thing's possession? That blade should've been with his grandfath- "... So that's it… Grandfather was also here… but he perished…" As Genichiro finished his thoughts, he looked up at the thing from the depths and asked it a question. "What do you want?"

"Human, it's not what I want. What do you want? Let me guess. To break free from these chains? To burn Inazuma to the ground? To claim the heads of those responsible for your predicament? I can offer you all that, as well as this blade you seem to be familiar with. All I ask in return is one thing."

"... That is?"

"Join me and the Order I belong to, and together we can grant all that and more."

"..." Genichiro merely nodded his head in response to the thing's offer, and with that, the Abyss Herald let Genichiro free, breaking his chains and burning the talismans, while handing him the Black Mortal Blade. As soon as Genichiro grabbed the blade, the Abyss Herald turned around.

"It's just as that machine said. To think we would be one step closer to our goals because of a few Outlanders. Hehehe, soon, all that will remain is The Aby-"

Stab.

"... Wha-" The Abyss Herald looked down to see a blade with an ominous black aura sticking out from his chest. "... You… why…"

"As if I'd ever pledge myself to a legion of disgusting creatures like yourselves. I will burn this nation and rebuild Ashina with my own two hands. And then, I will annihilate every threat to her, including you disgusting depth dwellers." Genichiro charged the Black Mortal Blade before slicing upwards, cutting the Abyss Herald in two. "Farewell."

"... Your… High… nes… s" The Abyss Herald turned to ash as it uttered its last words. Genichiro stretched his arms and legs after weeks of inactivity, before looking at the Black Mortal Blade in his hands.

"I understand Grandfather… Ashina will soon be rebuilt. And this time, there will be nothing that can harm her."

—-

Extra: The Generals

Through some sheer miracle, Sara and Genichiro were witnessing the duel between the Raiden Shogun and the Sword Saint, the both of them cheering for their respective idols.

"FACE IT ASHINA, THE SHOGUN IS THE GREATEST WARRIOR OF THEM ALL!"

"IMPOSSIBLE, GRANDFATHER IS THE PINNACLE OF STRENGTH, HE HAS NEVER KNOWN DEFEAT!"

The two continued to argue on and on about who was stronger between the two. It got so loud to the point Isshin and Ei stopped their duel to see the two bickering.

"Sigh… I'm sorry for my grandson's behavior. He's a bit… passionate to say the least."

"No need for apologies. General Kujou can be quite emotive herself."

"Heh… I guess we both have our hands full don't we?"

Ei gave a light chuckle before responding, "It appears so."

—-
Notes:

Welp, that's Isshin Ashina VS Raiden Shogun done. If you got this far, hope you enjoyed reading it as much as I did writing it. The next story in this series I'm planning will either be one of the two below.

Demon of Hatred VS Thunder Manifestation
Owl VS Ayato

Whichever one gets more comments on what they want to see will be the one that get's made first.

Leave a review, comment and criticize. Starting from the next arc, I'm planning on engaging more with notes at the end of each chapter instead of each arc.

Again, thanks for reading. Review, comment, and criticize.