Before the fight of the century could start, the team had to find one blond idiot who ended up sleeping outside after quarrelling with a kid even younger than him.
Sukuna wasn't worried about Naruto; even if the story didn't go as it did in Canon, Naruto's furry friend inside him wouldn't let the knucklehead die that easily.
It didn't take very long before they finally found him; both Karin and Sukuna were excellent at sensing.
"What! Sukuna and Kakashi sensei are sparring? Why didn't you tell me earlier?" Already forgetting his meeting with the beautiful sister from earlier—though the sister part is questionable—with whom he engaged in philosophy, Naruto ran like his life depended on it to catch up to the fight.
There was no way he was gonna miss this out.
"And who was the idiot who passed out outside in the open? For god's sake, how come you're still alive is beyond me." Karin chided—typical sister berating her younger brother.
Naruto had that aura of being the mischievous younger brother, no matter how old he got.
Back at their makeshift training grounds, Kakashi and Sukuna faced each other—one sporting a lazy 'Let's get it over with' attitude, while the other looked forward to the fight.
Once they were done with their stare-down, without a word, they both moved.
Sukuna was the first to strike—a blur of motion, his fist cutting through the air. Kakashi blocked with his forearm but immediately felt the raw power behind it. His feet slid back several inches across the dirt.
"Strong," Kakashi muttered, shaking off the numbness in his arm. A certain youthful friend of his would approve of this boy here a ton.
Sukuna didn't reply. He darted forward again, his palm striking toward Kakashi's chest. Kakashi twisted, dodging just in time, and countered with a low kick aimed at Sukuna's leg. Sukuna leapt over it, spun midair, and launched a kick that nearly connected with Kakashi's jaw.
Kakashi ducked, feeling the wind slice past his head. "Kid, what the heck do you eat," he said, half-impressed, half-winded.
"Curses," Sukuna smirked, stepping in close.
"Once you develop a thick skin, you get used to it."
Their fists and feet collided again and again, each impact echoing through the trees. Kakashi realized quickly that this wasn't an ordinary genin-level fighter.
Hell, he knew it before he even started, but he didn't know that just being serious for this fight wouldn't do—he had to actively participate.
First of all, Taijutsu wasn't where he wanted to be against someone like Sukuna.
Sukuna's movements were sharp, disciplined—closer to an elite chunin or even jonin in raw physical ability.
Watching from the sidelines, Naruto grinned widely. "C'mon, Kakashi-sensei! Knock that smug look off his face!"
"Yeah, hit him hard for us!" Karin yelled, crossing her arms.
Sakura chimed in too. "You better win, Kakashi-sensei! That jerk still owes me for the bruises he gave during training!"
Sasuke smirked faintly but didn't cheer—his Sharingan eyes followed every move, studying. Nothing useful to himself exactly had come up yet for him to copy; however, it's only a matter of time. Until then, he'd just enjoy the fight.
Sukuna's brow twitched at the noisy chorus. 'Really!'
'I did so much for them, and this is how they repay me. This world really knows no loyalty.'
Kakashi used that brief distraction to strike. He swept forward, landing a clean hit to Sukuna's side. But Sukuna barely flinched. He wasn't holding back in this fight; his CE enhancements were on point. Nothing less than a Chidori was leaving a mark on him at this point. He grabbed Kakashi's wrist mid-motion and yanked him forward, driving his knee toward Kakashi's ribs.
Kakashi twisted, escaping with minimal impact, but his breathing quickened. Stamina was his bane for as long as the story was serialized.
'If he lands one solid hit, I'm in trouble,' Kakashi grumbled and made sure to weave out of the way every time before those heavy punches landed on him.
Time to change tactics. Kakashi leapt back, forming quick hand seals. "Fire Style: Great Fireball Jutsu!"
A huge burst of flame roared toward Sukuna.
"Resorting to Ninjutsu this quick? Come on, Kakashi, you disappoint me." Sukuna sighed. He knew the man was gonna pull Ninjutsu even after they'd nonverbally agreed to keep it Taijutsu only.
His excuse most likely would be, 'A ninja has to be ready for everything,' or 'There is no fairness in ninja fights. We are not samurais.'
Sukuna just snorted and got ready.
"Curse Technique Reversal - Freezer."
Potent Reverse Curse Energy went into his technique, reversing the very nature of its application. Once a furnace fueled by cursed energy turned into a place where heat couldn't survive.
The temperature dropped so sharply that moisture condensed at a rapid rate, and the next second, as soon as Sukuna swung his arms around, a wall of ice formed in front of him.
The incoming fireball collided with the newly formed wall of ice; the contact gave birth to vapor and utter disbelief inside the audience.
"What! How did he do that? Since when can he do that?"
"Isn't that the masked man's ability—to make ice? Is Sukuna from that same clan?"
"A Kekkei Genkai? But how is that even possible?"
Everyone was shocked at what Sukuna just displayed; even Kakashi was stupefied at the boy's action.
However, Kakashi barely had time to recover before Sukuna was in his face again—his fist grazed Kakashi's cheek, the next hit driving him backward. The Copy Ninja barely caught his footing, sliding to a stop.
Naruto was laughing. "Whoa! Kakashi-sensei almost lost his mask!"
"Don't let him bully you, sensei!" Sakura added. Out of personal experience, but she wouldn't agree—nope, not happening.
Kakashi's brows twitched with incredulity. Who's bullying who? He's supposed to be the sensei here.
But that move from Sukuna really got to him. 'How did the boy do it?'
Even his Sharingan couldn't copy Bloodline Limit abilities.
As for how Sukuna really did it, it was pretty straightforward. His furnace was the key. Running RCT into it and boom—they got ice.
Easy!
They wouldn't get it though.
In fact, this was the exact way how Sukuna was able to copy Megumi's Water Piercing technique he pulled off with Max Elephant's water when he was in possession of Megumi and his Ten Shadow technique.
On one hand make ice and on the other fire, maintain the balance to only condense water and then condense it to the point pressure is generated. Then just release it.
Simple, right!
Nope!
It was hard as fuck. He had to go through many hoops to achieve it and even had to resort to an entire chant to use that ability. Not a practical technique by any means—he created it to have better control over his techniques and train rather than actually use it in a fight.
Back to the fight.
Kakashi took the chance to grab Sukuna's arm and flip him—the question about his Ice Release could wait for now—but Sukuna landed like a cat and lunged again. Their strikes blurred together—punches, kicks, blocks, parries—all too fast for the genin to follow.
Finally, Kakashi jumped back again, panting lightly. Again, stamina deficiency issue.
"You've got some terrifying Taijutsu. Now I almost feel bad for the kids." He almost gave a sympathetic look to his genin.
"True, but you're have to say it's fun though," Sukuna said flatly, rolling his shoulder.
"Heartless bastard."
"Beat him, Kakashi sensei! Avenge us!"
"Get the bastard, sensei!"
"HM."
Kakashi smirked beneath his mask. "Seems like you ain't that popular, kid."
He weaved another set of signs—this time water surged up from the nearby stream. "Water Style: Water Dragon Bullet!"
A twisting serpent of water roared toward Sukuna. The cursed fighter dashed sideways, the wave grazing his shoulder. He pushed off a tree trunk, launching himself high before crashing down in front of Kakashi, landing a heavy punch into the older man's guard.
The impact forced Kakashi backward several feet. The ground cracked under his heels.
"Damn," Kakashi said softly, shaking his arm again. "You really don't hold back."
Sukuna grinned faintly. "Believe me, I'm."
Kakashi frowned at that. Was the kid pulling his leg? But what if he's not? Is he really still holding back?
Before Kakashi could answer, Naruto shouted, "Get him, sensei! You can't lose to a guy who can't even do ninjutsu!"
That one stung Sukuna's pride.
"A second please."
He appeared behind Naruto in a flash, flicked his forehead hard enough to send him tumbling. "Say that again, brat."
"Ow! That's against the rule! No hitting the audience!"
And the next second he was back in front of Kakashi, throwing another punch.
...
A/N : I honestly don't get it why in the entire series only Gojo use the reverse nature of his technique. Not even Sukuna does it, it baffling almost.
Why wouldn't you explore that side of your power ?