Kaien watched as a dizzying blur of Shisui's afterimages and Itachi utilizing incredible speed to engage Kakashi in a melee. "I have to remove his Sharingan first," Kaien thought. "I can't risk fighting him with possibility of him awakening his Mangekyou Sharingan. Luckily, Shisui and Itachi are keeping him occupied. Shifting a seal inside body such as to eyes requires an immense amount of focus."
Closing his eyes, Kaien carefully manipulated the negative seal from Kakashi's blade he placed earlier, shifting it onto his exposed Sharingan. He watched Kakashi's three-tomoe Sharingan spin, to keep up with Shisui's Body Flicker technique.
If Kakashi had kept his eye closed, the trick never would have worked. "Good," Kaien muttered under his breath. The negative seal was perfectly placed onto the cornea of his eye socket. Now, I just have to drag it out carefully without severing the optic nerve completely.
Kakashi suddenly gasped, feeling a tug on his left eyeball. "Wait... this feeling..." his mind panicked. "It's the same seals he used on me and Guy. When the hell did he place it?" Then, he realized it was at the moment he jumped on him. His rage got the better of his judgment.
Shisui eyed Kaien, who gave a subtle nod. Just then, Shisui's assaults grew twice as fast, forcing Kakashi onto the absolute defensive. To follow Shisui's lethal blade work, Kakashi needed the tracking of the Sharingan. But if he kept it open, the unseen pull would rip it right out of his skull.
Prioritizing to preserve Obito's memento above all, Kakashi tightly clamped his left eye shut, forcing himself to fight Shisui and Itachi with only his remaining normal eye.
"All according to plan," Shisui thought, maintaining a relentless pressure to ensure Kakashi couldn't deduce the true nature of Kaien's plan.
The forced handicap was catastrophic for Kakashi. Defending blindly on his left side, he missed a feint. Shisui's blade flashed through the air, leaving a bleeding gash across Kakashi's right cheek.
Upon contact with the blade, a new seal from Shisui's blade was implanted onto the bloodied skin of Kakashi's cheek.
Kaien watched the trap succeed. "Step two complete."
With a flick of his wrist, Kaien shifted the new seal from the cheek onto Kakashi's normal eye. Unlike the Sharingan, Kaien had absolutely no use for this ordinary eye. He clenched his fist and yanked backward with everything he had.
A sickening wet pop echoed. Kakashi's normal right eye was torn from its socket, flying through the air before landing in Kaien's palm. Without a shred of hesitation, Kaien squeezed his fingers together, crushing the eye into nothingness as blood spilled from Kaien's hand.
Kakashi stumbled back, blood pouring from the empty right socket while his left eye remained tightly clamped shut to protect Obito's momento. He was now truly blind, caught in a nightmare scenario: either open the Sharingan and risk losing his best friend's final gift to the enemy, or stand his ground and fight the trio in the dark.
A bitter thought came through his mind just before he resolved to use the Flying Thunder God Kunai. "He felt pathetic, almost sad, that every time his life hung in danger, he had to summon his depressed sensei to bail him out."
Dropping from the tree trunk, Kaien's sandals hit the ground. The moment his feet landed, he exploded forward, bolting toward Kakashi at a blinding speed as his seals boosted his speed, as adrenaline surged through him. He couldn't believe that, after all this time, his vengeance was finally within reach. As he blurred through the forest, his fingers flicked through a sequence of hand seals.
"Yin Release: False Distortion!"
A colorless, odorless Yin chakra flooded the atmosphere, bleeding silently from every one of his tenketsu points. Completely blind to the situation closing in around him, Kakashi relied on his defense.
"Earth Release: Great Dome!"
The ground upheaved, enveloping him in a protective shell of solid rock. Buying himself a fleeting moment to think, Kakashi bit his thumb, smeared blood across his palm, and slammed it down to summon Pakkun. He desperately needed the ninken to act as his eyes. But the moment Pakkun manifested in a cloud of smoke, the hound's sharp senses were instantly ensnared by the warping effects of Kaien's unique Yin technique.
Kaien grinned, his chakra reserves had swelled massively since the Four-Tails had been sealed inside him, and he intended to use every bit of that power as he gathered the water chakra at his fingertip.
"Water Style: Drill Gun!"
A high-pressure torrent of spiraling water erupted from his fingertip, slamming into the earth dome and blasting it into wet rubble. Yet, when the spray cleared, the crater was empty. Kaien snapped his gaze upward. High on a thick branch, Kakashi stood with Pakkun perched firmly on his shoulder.
Pakkun scanned the area, but before he could give a warning, his eyes met with Shisui's for a fraction of a second as his Sharingan instantly locked the dog in a paralyzing Genjutsu. Kakashi immediately channeled a pulse of chakra, snapping Pakkun out of the illusion.
"Don't look into the Sharingan," Kakashi warned Pakkun as he blindly raised his hand as the high-pitched chirping of a thousand birds filled the air as his Lightning Blade crackled, pointing into the their direction. Beneath him, the trio... Kaien, Shisui, and Itachi... landed shoulder-to-shoulder in unison.
Kakashi had reached terrifying heights after grueling training sessions with his reanimated father, Sakumo Hatake. As he swung his blade in a sweeping arc.
"White Fang Style: White Slash!"
A crescent wave of brilliant howling lightning chakra tore out. The trio scattered, leaping high onto the branches just as the slash sheared through the massive tree trunk they had stood upon, continuing onward to obliterate a massive swath of the forest behind them.
"Shisui is at eight o'clock!" Pakkun guided his partner.
Kakashi flicked across the branches, throwing a barrage of omnidirectional slashes rapidly that it rendered Shisui's Body Flicker technique entirely useless. Shisui blocked a desperate blade strike, only for Kakashi's body to suddenly burst into blinding current.
"Lightning Release: Shadow Clone Technique!"
The lightning coursed through Shisui's body. Kakashi's voice cut through: "One down."
But it was an illusion. The figure Kakashi had struck suddenly splintered into an ordinary wooden log. Just as Shisui and Kakashi had been about to collide, Kaien had yanked Shisui backward onto a branch with his seals, his False Distortion technique actively feeding warped data to Pakkun and, by extension, to Kakashi's ears. And they still believe they had struck Shisui.
~~
A/N: so the trio fight, mostly Shisui doing the job and Itachi helping here and there. And Kaien prepping his seals. This is by no means an easy fight.
If the sharingan was open, Kakashi would have immediately sensed something was wrong and Kaien knows it too and that is why the prep.
A point to note, Kaien has already placed seals on his teammates before fight.
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