Kazuo's chakra quickly flowed through his hand, coating it entirely in a faint sheen of blue as he made a clawing motion, his fingers as if they were sharp claws tore right through his own flesh and blood and into his body, wrapping around his own heart before he started to pull it out.
Blood instantly spewed as if it was a geyser from his chest, his expression however maintained an almost bored facade, his eyes didn't show any pain whatsoever, it was as if he was simply plucking a hair from his head.
*Sqlchkkk*
Finally with one last push, his heart was fully clawed out of his own chest, looking down at the organ that was still faintly beating, the last spasms of the muscle that had been inside his own body.
Right on top of the organ, dozens of black kanji like symbols could be seen almost covering the entire surface.
'First order of business is to expand the seal.' Kazuo thought inwardly as his shadow clone moved next to him as he placed the heart on the ground.
The first shadow clone slowly grabbed his real body and laid it on the ground before its hands glowed with a faint green sheen as it started to use chakra to start pumping blood throughout his organs, and most importantly his brain.
Acting in a way like an artificial heart, this was the way that Kazuo had devised to increase the already short amount of time he would have to study the seal during each time loop.
The other shadow clones meanwhile gathered near the heart and made hand seals, in an instant the seal that was placed upon the heart expanded, covering the entire heart until it was almost entirely pitch black from the large ammount of kanji and specialized characters inscribed upon it.
"First, start researching the central cortex of the seal, thats the main focus, destabilizing the main cortex usually leads to the seal being broken. Then as we proceed we can see if there are any fail safes in place on it so that if destabilization does happen the seal automatically goes off, with how detailed madara's plans had been, I doubt that he would have made it easy." Kazuo's shadow clone muttered as they all quickly started looking at the heart in detail, trying to memorise as many of its details as possible.
Three shadow clones were focused on the main cortex whilst the two others were focused on simply remembering the other parts of the seal.
Minutes slowly crawled by and slowly the real Kazuo started feeling his eyelids start to close, the amount of time that he now had left was merely a minute at best.
Turning his gaze to the shadow clones, he quickly dismissed them, gaining all the information they had gathered before seing another wave of chakra directly into his brain, leading to its collapse almost instantly.
The world once more stopped, the colours fading out before the reversal process started once more.
After an unknown amount of time, the world regained its colour, time had once more been rewound. Opening his eyes, Kazuo found himself back sitting on the ground, his chest was no longer an open clawed wound, it was as if nothing had happened, because nothing had in reality, in this time line.
'Let's continue' Kazuo thought to himself as he once more created the shadow clones and proceeded with the repeating the same process.
Ten time loop turns later, the amount of time he had after clawing his heart out increased slightly, he had gotten better at clawing the organ out with as little damage to the vessels around it as possible, allowing the shadow clone to more easily keep him alive.
Twenty Turns later, his time increased once more as his expertise on using medical ninjutsu increased, leading to the shadow clone more efficiently carrying out its purpose.
Thirty five turns later, the main cortex of the seal was finally around seventy percent memorised and around twenty percent of it was already researched and understood.
Fifty turns later, Kazuo lifted his hand, instead of simply covering it in chakra, he covered it in medical chakra, plunging his hand into his chest, he tore around the heart with a delicate manouver of his hand before pulling the organ out whilst at the same time regenerating as many of the vessels as he could.
Finally once the heart was pulled out of his own chest, the chest itself looked almost completely fine, the vessels in his body were in the exact same location that they needed to be, the hole in his chest was gone, the only thing missing was his heart, where now on an empty space remained.
Blood continued pumping through his body with the help of his shadow clone however unlike what some might think, this didnt actually increase much of the time that he had, even if the blood continued flowing, currently his chakra control still wasnt quite at the level of perfection, this lead to the stress on the small veins inside his body to reach such levels that after a few minutes they would burst and cause internal damage.
The other part that he still couldnt quite replicate was the transfer of the oxygen throughout his entire body, the heart as an organ recirculated the blood and it also seperated the blood with oxygen that needed to be sent around the whole body with the one that was already used.
This was a sort of side challenge that Kazuo had created for himself, if he managed to truly replicate the entire process of his heart by his chakra alone, he could theoretically lose the need for the organ entirely, this would lead to one less fatal weakness in his body, increasing his capabilities as a ninja even further. All that was left to do now, was continue his practice on both the seal aswell as the perfecting of his own specialised medical ninjutsu.
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