The charcoal pencil veered across the paper, completely ruining the anchor unit structure he had only just started. Rinto stared at the crooked line, his hand frozen around the pencil for a long moment, then slammed it onto the stone workbench.
The structure was not wrong. He just could not settle down.
The moment the pencil touched the paper, the commotion from the day Orochimaru broke in flashed through his mind-the dull crash of the stone door being blasted open, blueprints flying everywhere in the shock wave, engraved metal plates falling to the floor and warping. Even though he had driven the man off afterward, he had spent an entire night redrawing the blueprints. The irritation of being interrupted still clogged his chest.
This island had long since stopped being safe. People from Konoha had come, Orochimaru had come-who knew who would break in next? If someone kicked down the laboratory door right when he was calibrating an anchor, at best the entire experiment would be ruined. At worst, chakra backlash would kill him outright.
"Fuck. Nothing but bullshit."
He cursed, stood up, gathered the senjutsu blueprints spread across the table, and locked them inside the blastproof stone cabinet in the corner, snapping two layers of seals into place. Then he turned to rummage through the defensive supplies in storage, haphazardly stuffing engraving knives, sealing metal plates, and conductive fluid for lightning release anchors into a backpack. He grabbed two hard, dry wheat cakes and tucked them into his clothes, then locked the laboratory's stone door and headed out.
He had no comprehensive plan. His previous defenses covered only the area around the laboratory and the main dock. Most of the remaining coast, cliffs, and dense woods were full of gaps. He would patch up the most important part first: the sensory network. At least if someone broke in, he would get ten or twenty minutes' warning instead of being cornered indoors.
He followed the coastline, finding a crevice in the rock face beyond the tides' reach every few dozen meters and burying a sensory anchor with scrambled-frequency camouflage. He had revised the anchor's structure countless times before. Its fluctuations were tied to the natural frequencies of the sea breeze and vegetation. Never mind a ninja's chakra-even a slightly larger seabird landing would register.
But on the beach, blueprints never had the final say. He buried over a dozen anchors that morning, only for the rising tide to soak them that afternoon. When he went back to test them that night, half had lost their signals. Early the next morning, he trudged over the wet sand left by the receding tide, dug the failed metal plates out, and hurled one against a reef in fury. The plate warped with a piercing clang.
Cursing did no good. All he could do was revise them. Squatting on the reef, he used the engraving knife he carried to modify the anchors' sealing structure on the spot. Sand and seawater coated his fingertips, leaving the engraved lines crooked. Halfway through, the linked-operation logic of the senjutsu anchors suddenly sprang into his mind. He drew two lines on the rock with his knife, then abruptly caught himself, cursed his own distraction, and returned to modifying the anchors.
He kept burying, revising, and testing them, running around for three or four days until blisters covered his soles before he finally finished placing sensory anchors along the entire island's coastline. During the test, he stood at the center of the island and could clearly sense even a crab crawling along the most remote cliff. Only then did he let out half a breath of relief. He leaned against a tree and took a bite of wheat cake. Crumbs lodged between his teeth, but he could not be bothered to deal with them.
Next came the middle belt of traps. He did not use explosive tags that blasted a whole area apart. His previous fight with Jiraiya's people had caused such a commotion that crumbs of stone had shaken loose from the laboratory walls. He combined dynamic configurations with sealing jutsu to create anchors that triggered in sequence: step on the first, and lightning release paralysis patterns would race up through the soles of the intruder's shoes, locking their chakra pathways outright; force their way onward, and a directional explosion release shock wave would follow, blasting only toward the intruder without damaging a single plant nearby; farther in waited an adaptive binding barrier that tightened harder the stronger the chakra fluctuations became. Even a jonin caught inside would need a long time to break free.
While laying the traps, he also cleared away the old seals damaged in the previous fighting. Some ancient seals left by the Land of Whirlpools interfered with his new anchors' frequencies, setting off a cacophony whenever they triggered. He had to dismantle them with extreme care, afraid of accidentally detonating their killing formations. When the work became unbearable, he would sit on the ruins and stare blankly at those centuries-old patterns, his mind circling back to senjutsu's responsive units. Sometimes he would study the patterns for ages before remembering that he had come to dismantle traps, not conduct research.
Several more cycles of nightfall passed before he sorted out both the outer sensory network and the middle traps. He had already lost track of how many days he had spent running around outside. Sand, mud, and resin stained his clothes. Branches had scratched several small cuts into his arms, which scabbed over only to be scraped open again, but he paid none of it any attention. All he knew was that when he returned to the laboratory at night and sat on the stone stool, every bone in his body ached. He could fall asleep the moment he lay down, and even his dreams were filled with anchor patterns.
He had thought that would be the end of it. He could tidy up, return to the laboratory, and get back to tackling the hard problem of senjutsu. But when he came around to the Martyrdom Sealing ruins at the island's center, his steps halted.
He had always given this place a wide berth. When the Land of Whirlpools fell, its last ninja had laid the Martyrdom Formation with their lives. He had once accidentally touched its outer patterns, immediately triggering a spatial seal's counterattack and nearly getting dragged into another dimension. Previously, he had been too busy with senjutsu to bother with this time bomb. But now that he wanted to connect the whole island's defenses, this place was the biggest gap.
No one knew where this seal's trigger boundary lay. If the shock waves from a fight struck it one day and sent the entire island's seals into a frenzy, his laboratory and the materials he had spent over a decade collecting would all be blasted to ash with it. Moreover, the formation concealed the Land of Whirlpools' most fundamental sealing logic. Most of the fragments in the incomplete scrolls he had practically worn out reading were rubbings taken from its outer sections. If he could truly understand the responsive structures inside, it would be genuinely useful for both patching his defenses and optimizing his senjutsu anchors.
Rinto stood outside the ruins' warning line, hesitated for less than half a minute, and took off his backpack.
There was no avoiding it. Rather than leave a bomb sitting there and live on edge every day, he might as well dismantle it thoroughly and understand it once and for all. If he could use it, he would. If not, he still had to disable its triggering mechanism so it would not get in his way later.
He did not dare touch it directly. First, he circled the ruins no fewer than ten times, copying every visible outer pattern into the notebook he carried. The more he drew, the heavier his heart grew. This was no single seal. It was dozens of formations with completely different functions, nested and linked together so that disturbing one part affected the whole. The outer warning formation, the middle killing formations, and the innermost martyrdom self-destruction formation were all tangled together. Touch one wrong line, and the entire island might go down with it.
For his first probe, he released only a thread of chakra finer than a strand of hair and touched an outermost pattern that looked unused. The instant his chakra made contact, a pale blue-green glow lit up across the entire formation. Countless wind blades erupted from the patterns on the ground, shooting straight at his face. Rinto reacted quickly, immediately withdrawing his chakra and raising an earth release rock wall with a sweep of his hand. The wind blades struck the stone, spraying rubble into his face. Even his mouth filled with sand.
"Fuck. That sensitive?"
He spat out the sand, a sheen of cold sweat breaking out across his back. Good thing he had not dared probe deeper. Otherwise, that strike would have been far more than wind blades.
He did not dare make any more reckless attempts. Carrying his backpack, he returned to the laboratory and dug out every incomplete scroll from the Land of Whirlpools piled in the corner. He went through them one by one, scrutinizing every page. Most were badly incomplete. Some had burned down to half a page; others were so worm-eaten that their words no longer connected. Working from the few surviving words, he pieced together the Martyrdom Formation's underlying logic bit by bit.
That search took another two days and nights. When sleepy, he leaned against the rock wall and dozed for ten minutes. When hungry, he took a bite of dry wheat cake, chewing until his jaw hurt, still unwilling to put down the incomplete scroll in his hands. Finally, from three different incomplete scrolls, he pieced together the formation's foundation-it was a distributed seal with no fixed formation core. Every sealing pattern on the island was an extension of it. Back then, the Land of Whirlpools' ninja had fed it with their own life chakra to perish together with the invaders.
Without a fixed formation core, he could not use the conventional method of breaking a formation: destroy its core first, then dismantle its perimeter. Moreover, all its anchors were linked. Disturb one point, and the entire formation moved. That was why touching an outer pattern had triggered the killing formation.
Only after understanding its foundation did he dare return to the ruins. This time, he had learned his lesson. He first placed three defensive barriers around himself and engraved an emergency spatial transfer anchor beneath his feet so he could escape immediately if anything happened.
He crouched on the ground as though defusing a bomb, releasing chakra thread by thread and probing inward along the outermost patterns. He traced the course of each line and its connections to the other formations, gradually completing the internal structure in his notebook. It was agonizingly slow. At the slightest sign of trouble, he immediately withdrew his chakra, hardly daring to breathe.
Once, his chakra accidentally touched a linkage node between two formations. The entire ruin instantly shook, and several narrow cracks opened in the ground, releasing an immensely powerful spatial distortion force. His three barriers crumpled into a single mass in an instant. Terrified, he immediately dispersed all his chakra and scrambled backward more than ten meters. He held his breath and waited nearly half an hour before the formation's fluctuations slowly subsided. Cold sweat had soaked the back of his clothes.
"Fuck, you're a real nightmare," he cursed through gritted teeth, his legs a little weak. Anyone else would probably have given up long ago, but as he watched the patterns slowly dim, something instead lit up in his eyes.
Though he had nearly gone down just now, he had seen the formation's core logic clearly-its anchors were not static. They adapted to chakra pressure. The more force you applied, the fiercer its counterattack became; the weaker your chakra and the closer it was to natural energy, the less it reacted.
That logic struck like lightning, hitting the senjutsu problem that had been stuck in his head for days.
The responsive anchors he had designed previously only let the anchors follow chakra flow. He had never figured out how to make them automatically adjust their locking strength and opening range according to energy pressure and flow speed. Yet this Martyrdom Sealing had taken "responsive adaptation" to its limit. Centuries ago, people had already engraved this logic of dynamic equilibrium into the very bones of their seals.
Rinto instantly forgot that he had come to dismantle a seal and eliminate a hazard. He simply crouched beside the ruins, set his notebook on his knees, and took up his charcoal pencil. Instead of drawing the seal's structure, he first drew the responsive anchor patterns he had just seen clearly, then studied them and picked apart their adaptive logic bit by bit.
He forgot the time, forgot his hunger, and forgot what he had originally meant to do. By day, he crouched beside the ruins, probing patterns, drawing structures, and conducting the most cautious tests. At night, he returned to the laboratory and organized the logic he had grasped that day by lamplight, revising his senjutsu anchor designs along the way. The synchronization and adaptation problems he had racked his brains over without solving actually all had answers within this centuries-old seal.
Only when the wheat cakes in his pockets ran out did he remember that he had gone almost a day without food. Before dark, he went to the shore to try to catch a couple of fish. He crouched in the shallows for ages with a sharpened branch, but failed to spear a single fish and only got his trouser legs soaked by the waves. Irritated, he flung the branch aside and went into the woods to pick a pocketful of wild fruit. It was so sour that his face twisted. After two, he could not stomach any more, so he returned to the ruins with the fruit tucked away and resumed poring over the patterns.
Another five or six days passed like this before he understood the Martyrdom Sealing inside and out. He did not destroy it, only modified its outer triggering logic. Instead of counterattacking ninja chakra indiscriminately, it would now react only to chakra used in malicious attacks. Not only would it no longer run wild at the slightest provocation, it had become the most central barrier in the entire island's defenses.
More importantly, he had fully mastered the underlying logic of the seal's responsive adaptation, distributed linkage, and equilibrium without a formation core. The gaps in his earlier senjutsu responsive anchor designs that had left him restless and irritable had all been filled without him even noticing.
By the time he headed back to the laboratory with his backpack, dusk was falling. The setting sun stretched his shadow long across the rubble and wild grass underfoot. He clutched his densely filled notebook, charcoal dust and dirt still coating his fingertips. Even as he walked, he was still working through the details of the anchor optimizations in his head, nearly tripping over a stone.
Back in the laboratory, he first grabbed the water dipper and gulped down half a dipper of cold water. Only after it reached his stomach did he recover from his whole-body exhaustion. He pushed aside the clutter on the stone workbench, spread out all the sealing structures and anchor optimization blueprints he had drawn over the past few days, picked up his charcoal pencil, and began redrawing the distributed responsive anchors for senjutsu.
The oil lamp's flame flickered, casting his shadow onto the rock wall. Outside the window, waves sounded one after another. Inside the laboratory, there was only the soft scratching of charcoal across paper. It was so quiet that nothing remained but him and the patterns on the page.
The irritation of being interrupted, the frustration of failed attempts, and the exhaustion of running around for more than ten days were all gone. All that remained was the ease of a clear path of thought and anticipation for the trial and error ahead.
He had never built these defenses or dismantled these seals to protect a deserted island. He only wanted to work in peace and quiet until he understood this whole business of chakra completely.