Chapter 34: A Major Discovery at the Barrier Division
Ishiro had planned these five days out well. Over the past year of sporadic experiments, he had nearly finished testing the fragments of the "Fire Domain" sealing technique. Out of the hundreds of fragments, the vast majority had been deciphered through repeated trials—only a small portion remained unsolved. Among those unsolved, some were incomplete in structure, or their function was too arcane to be easily patched in. Based on his overall analysis of the sealing layout, Ishiro had basically guessed their purpose. Now, only two fragments remained fully mysterious—two of the largest, and the ones that baffled him most.
Nonetheless, Ishiro's growth in fūinjutsu this past year had been substantial. Through many attempts and thorough examination of the entire technique, he hypothesized that one of those remaining fragments handled the "Fire Domain" method of flame generation, and the other involved channeling natural energy. Moreover, Ishiro had a decent idea of how to proceed with investigating them, but to implement the plan, he would need the Barrier Division's help.
Fortuitously, he had five days off. First thing in the morning, Ishiro headed to the Barrier Division and summoned all of the village's sealing experts who were currently in-town. Unlike last time, upon hearing that Ishiro was the one calling them, everyone came without hesitation.
Once they had gathered, Ishiro spent an entire hour describing to them his year-long approach to dissecting the "Fire Domain" technique—how he divided it into pieces, his experimental methodology, and his high-level findings. Naturally, he only disclosed the conceptual results; actual in-depth knowledge wasn't something to be shared freely due to internal confidentiality rules.
Even so, the audience was stunned. Most of them were still immersed in B-rank fūinjutsu studies. A few top-tier sealing masters like Mizuhara or Bunji (names as examples) had begun tackling A-rank techniques, but S-rank materials remained so far beyond them that they'd barely scratched the surface. They certainly wouldn't dare attempt to break down an S-rank seal as Ishiro had. Yet Ishiro had actually done it, gleaning some real insights.
Officially, Ishiro's primary role was as a member of Team Five. Strangely enough, he never lost his Barrier Division posting. In fact, he continued drawing a salary from them each month, and they supplied him with the materials for his sealing experiments. The reason was simple: the upper management believed Ishiro's sealing talent would eventually surpass theirs, so it was wise to keep him favorably disposed to the Division.
Sure enough, just that one-hour talk describing his research ideas justified his monthly pay on its own.
Finally, Ishiro explained that two fragments remained unsolved, and he outlined his guess of what they did. The entire Barrier Division went wild. None of them were fools—once you imagined the possibilities, you realized that fully deciphering how to harness natural energy in a sealing technique could shake the entire shinobi world.
Of course, it wouldn't come easy. Even the Uzumaki clan members who'd designed "Fire Domain" clearly hadn't deciphered the full principle of converting natural energy. Otherwise, they'd have developed a systematic approach to senjutsu by now.
Yet even if they never grasped every underlying principle, simply reproducing such an energy-conversion effect experimentally would be massive. Who knew what sort of "forbidden arts" they could derive from it?
Consequently, everyone dropped their current tasks and focused on these two fragments. Unsurprisingly, news of this effort reached Onoki. Not only because Onoki possessed strong sealing knowledge himself, but also because having Onoki on board would help speed the project along.
Indeed, upon hearing about Ishiro's progress, Onoki began devoting part of his schedule each day to the research. As one of the greatest figures in the ninja world, he had a wide perspective and offered many suggestions.
Ishiro's five-day break was too short. The difficulty of cracking those two fragments exceeded his expectations. Even in that time, the research team barely advanced past a conceptual design phase. They had too many brainstorms, so they had to sort out which were feasible, which required lengthy or expensive experiments, and so on. They decided to select the most promising routes for initial testing.
Ishiro still profited tremendously, even though he couldn't remain at the lab day and night because of his Team Five duties. Moved by his achievements, Onoki personally granted him an A-rank mission reward—5,000 contribution points. This sum accomplished Ishiro's short-term goal at once.
Wasting no time, Ishiro immediately redeemed his coveted sensory ninjutsu.
Unlike battle-oriented jutsu, sensory techniques are classified under "pre-combat preparation," so they don't require high seal speed. That's partly why they're so expensive. Once Ishiro obtained it, he rushed home to read. After years of intensively studying ninjutsu and fūinjutsu theory, he found no trouble understanding this technique.
Grasping the core principle, Ishiro started practicing. As expected, sensory ninjutsu hinged on strong spiritual power—exactly Ishiro's forte. So his very first attempt succeeded. It was his easiest mastery in five years of transmigrating.
After finishing the seals, Ishiro pressed a single finger on the floor. Following the instructions in the jutsu's scroll, he used chakra to extend his mind outward. It felt miraculous, like an invisible hand probing all around. The feedback formed an internal mental image.
This process only took seconds. In that short time, Ishiro had scanned his surroundings. Yet the technique had limitations: it only detected living or energized entities. In Ishiro's perception, the area was full of many faint life signals, each like a barely visible smear of light. Meanwhile, a few large "suns" overshadowed everything around them—shinobi whose chakra was especially dense. Per the scroll, Ishiro trained himself not to lock onto those "suns," but to avoid them, so as not to overload or distort his feed.
He played with it a long while, watching in amazement as those auras moved about—some entering his range, some departing. They apparently remained oblivious to his detection. He was delighted. "It's totally worth the 10,000+ points," he thought.
Since Ishiro's spirit was so robust, he didn't feel fatigued even after a long session. Then he canceled the technique, went out, and walked the neighborhood, cross-referencing real objects with the mental images from his sense scanning. Thus he pinned down the technique's effective range. After a short while, he fully mastered it—a brand-new skill. Ishiro felt overjoyed.
But it was already late. He had a mission tomorrow, so he called it a night.
Next morning, Team Five assembled again. Kitsuchi eyed Ishiro with a hint of amusement—clearly, he'd heard how Ishiro had once more stirred up a sensation in the Barrier Division. But ninjas valued secrecy, so he didn't probe further. They proceeded as usual to pick a mission.
Ishiro, however, informed his three teammates: "Yesterday I learned a sensory ninjutsu. My detection range is around a hundred meters, and if I focus in one direction, it can extend to about three hundred. Let's pick a mission that can use it." He believed sharing his new skill was logical—concealing it might cause a slip-up in battle.
Shouhara felt exasperated. "Another ninjutsu? That easy, huh?" He was both envious and annoyed. Exactly where did Ishiro keep getting points and advanced scrolls?
Tanaka, likewise, admired it. During missions this year, Shouhara as the "heavy-hitter" had proven most useful, while Ishiro's ninjutsu, though limited, often distracted the enemy enough that they couldn't unleash their full power. Tanaka, a speed-based kunoichi, had mostly just hovered, launching small harassing attacks with her kunai. Now Ishiro had a detection skill on top of everything else, making him even more integral to the team, whereas she didn't feel her own improvements had been so dramatic.
In truth, it wasn't Tanaka's fault. Speed-based ninjas eventually become terrifying once they outrun their enemies by a wide margin—but early on, the advantage is small. One-on-one, you might stalemate an enemy, neither side hitting the other effectively, but in group combat, that enemy might just ignore you and focus on your allies. If you're up against foes who are genuinely strong, they're likely also quite fast, so your speed edge vanishes. Tanaka had been saving her money to buy the Body Flicker Technique, hoping to replicate the approach used by that chūnin (nicknamed "Takeman") from their first mission encounter. A well-timed Flicker let him break Ishiro's casting. Without Tanaka's hidden speed boost, Ishiro's jutsu would've been interrupted.
Oblivious to their thoughts, Ishiro eagerly flipped through the mission postings. Soon, they found a search-based mission. A local child had gone missing and the family posted a request for help retrieving him.
To be honest, in these times, a missing child usually meant tragedy. If it happened inside the village, security was better, and a wandering shinobi might simply find the child lost in some corner. But out in a small town far from the city, once a kid disappeared, the odds were bleak.
Ishiro hesitated briefly but ultimately chose it for the chance to test his sensor technique. His teammates also wanted to see how well it worked.
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