"Since you already know the details of the technique, and with Lady Tsunade and Lady Katsuyu watching, what exactly are you afraid of?"
Tsunade's tone left no room for hesitation. "With your level of chakra control, as long as you stay focused, you'll avoid causing any harm," she added, gesturing for him to begin.
Kyuushin hesitated only for a moment before nodding. "Then I'll give it a try." Tsunade's reasoning was solid, and her confidence in him erased his last trace of doubt.
She stepped aside, giving him space to work. Kyuushin mentally reviewed every step she had demonstrated earlier. After confirming the sequence was correct, he activated his First Stage Gene Lock.
Focusing on the spot Tsunade had indicated, he formed a precise chakra scalpel and made a clean incision, his movements steady and exact. Then, with a subtle exhalation, he gathered the water in the basin into a smooth, controlled sphere.
This next part was the most critical—guiding the sphere through the wound without damaging the organs. But under the heightened sensitivity and control of his Gene Lock, the process was unexpectedly seamless.
After withdrawing the darkened water—now heavy with extracted poison—Kyuushin placed it in a basin. Tsunade nodded as she observed his work. "Good. You've got it. Repeat the process until the water no longer darkens. Once it stays clear, close the wound."
Kyuushin gave a single nod and continued. He performed the extraction several times, each one smoother than the last, until the final sphere came out pure and transparent. Finally, he closed the incision with delicate chakra control, sealing the wound cleanly.
But when he turned around to report, Tsunade was gone. Instead, Doctor Zenbu stood beside him, calm and observant.
"Lady Tsunade left after confirming you'd learned the technique," he explained.
Kyuushin had just finished and was ready to collapse from exhaustion when Zenbu spoke again. "Wait. She also asked that you record all the steps of this ninjutsu on a scroll for further study."
Kyuushin paused mid-step, a wry expression forming. That was precisely the kind of thing Tsunade would request.
Zenbu, noticing the fatigue on his face, softened his tone. Even the strongest shinobi had limits, and Kyuushin had been pushing his for nearly two days straight—first fighting the Rain shinobi, then sustaining Katsuyu's chakra, while learning and assisting in surgery. It was already deep into the night, and his body could barely hide the strain.
Still, Kyuushin understood the gravity of the situation. If more poisoned soldiers appeared later, there would be no way for just Tsunade and Zenbu to handle it all. He needed to make sure other medical-nin could learn this technique.
Wordlessly, he sat at a nearby table, unrolled a blank scroll, and began writing. His brush strokes were steady, swift, and confident. Having watched Tsunade perform the ninjutsu repeatedly—and performed it himself—he recorded every detail from memory, from chakra flow adjustments to hand seal timing.
Zenbu nodded in approval and quietly stepped outside, leaving him to work.
When Kyuushin finished, he stretched his stiff hand and looked up. Zenbu had returned with a steaming plate of food.
"Thank you, Doctor Zenbu," Kyuushin said as he handed over the scroll, accepting the meal gratefully.
"It's I who should thank you," Zenbu replied sincerely. "You've done more than enough tonight."
As the deputy head of the medical camp, Zenbu was no novice. Yet, even he relied on Kyuushin's help now—not only for field care but for teaching newly developed techniques that could save lives. Gratitude shone openly on his face.
After handing off the notes, Kyuushin finally retreated to rest. For the first time in days, he allowed his body to relax fully.
The following days passed quietly. Although the Land of Rain and Konoha had officially severed ties, no large-scale clashes occurred. Either Hanzo was planning something new, or the previous failed raid had made him cautious.
Kyuushin still spent part of each day in the medical camp—not to heal, but to instruct the other doctors in the "Delicate Illness Extraction Technique." The scroll was helpful, but not everyone could master a ninjutsu just by reading. Under his guidance, however, progress was swift.
Teaching didn't consume much time, and with his current status, Kyuushin no longer needed to handle ordinary chores. The rest of his time went into training.
At this point, physical conditioning no longer meant much for him. Each activation of his Gene Lock naturally enhanced his body beyond normal limits. His focus now was refining his chakra's nature transformations. He had already perfected Wind, Water, and Lightning Release—only Fire and Earth remained.
However, these two required external chakra samples. Back in Konoha, Mito had prepared them for his training, but now, far from the village, those reserves had long been depleted.
There were plenty of shinobi in the camp, but most were genin who hadn't even begun Nature Transformation. Uchiha Fugaku possessed Fire Release, but their relationship wasn't close enough for Kyuushin to ask for cooperation without raising questions.
Even the Third Hokage knew nothing about his Gene Lock abilities or special training. Only Mito did. Revealing his secret now would be too risky.
Still, he wasn't without other goals.
The boast he had once made to Mito hung in his mind—a promise he intended to fulfill: to master a Bloodline Limit.
He had already mastered three base elements: Water, Wind, and Lightning. Water and Wind together could form Ice Release. Water and Lightning could create Storm Release. The combination of Wind and Lightning wasn't known in recorded history, but theoretically, it should be possible.
Yet, this mysterious mix wasn't his priority. His immediate options were clear—Ice Release or Storm Release.
Originally, Kyuushin had planned to attempt Bloodline Limit fusion only after mastering all five chakra natures. With all of them, his choices would multiply: the famed Wood Release of the First Hokage or the devastating Lava Release used by shinobi of immense power.
After some thought, though, Ice Release stood out as his best option.
Wood Release carried too much political weight in Konoha. If he displayed that power now, the villagers would lose their minds, and the elders would face chaos. Many might even want to name him Hokage immediately—something that would throw the village into turmoil.
Wood Release could come later, once both Konoha's leadership and its people were mentally prepared.
As for Lava Release, its many forms—magma, lime, and rubber—were too unstable to control without experience. It would be better saved for the future.
Other Bloodline Limits such as Boil Release, Magnet Release, and Explosion Release each had glaring weaknesses despite their destructive potential. None suited his long-term vision.
Ultimately, Ice Release aligned perfectly with Kyuushin's needs—versatile, balanced, and efficient.
And so, with his mind clear, he began focusing all his will on forging the first Bloodline Limit that would bear his name.
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