The Fire Thief's Price and the Undercurrent

Uchiha Sou struggled through endless darkness and splitting headaches for what felt like an eternity.

His consciousness was like a sunken ship, trying again and again to surface above the icy sea, only to be dragged back into the abyss by an invisible force. Faint cries seemed to echo in his ears, along with the clash of weapons and a low, warning hum from the very foundations of the world.

At last, a gentle yet resilient stream of Chakra, like a trickling brook, steadily nourished his nearly depleted pathways and mindscape, slowly pulling him back to reality from his deep coma.

He struggled to open his eyes. His vision remained blurred for a long while before gradually clearing. The familiar ceiling came into view—it was his home in the Uchiha Clan Compound. It was already late at night outside, and only the occasional insect chirped.

The slightest movement brought a violent headache and a bone-deep ache, as if every muscle in his body had been torn apart. He couldn't help groaning.

"You're awake?" A slightly weary but concerned voice sounded.

Uchiha Sou turned his head and saw Izuna Uchiha sitting in a chair nearby. His face was still somewhat pale, so clearly his own injuries had yet to heal completely. A medical ninja was putting away their instruments, apparently having just finished a round of treatment.

"Lord Izuna..." Sou's voice was hoarse and dry as a cracked gong.

"Don't move. You've overexerted yourself." Izuna motioned for him to lie still, looking at him with a complicated expression. "The Medical Corps says your body was practically hollowed out. Your Chakra pathways are torn in several places, and your mental energy is nearly exhausted. What exactly did you do?"

Sou's heart tightened. He obviously couldn't tell the truth, so he could only make up an excuse. "At the time... I saw Lord Madara in danger, and in my panic... my Sharingan seemed to... overexert itself... I was trying to see the shadow that attacked him..." The explanation was half true, half false, but it made sense.

Izuna studied him for a moment, seemingly trying to read something in his eyes. But Sou's eyes held only weariness and weakness, and his Sharingan was closed.

"Don't push yourself so hard next time." Izuna finally sighed, his tone softening. "You did well. Although you couldn't stop my brother from being injured, if you hadn't warned us in time"—he mistook Sou's interference with Causality for a warning from the Sharingan—"the consequences would have been unthinkable. My brother specifically asked me to look after you."

Sou blinked. Madara had asked Izuna to look after him? That was unexpected.

"Lord Madara..."

"My brother's injuries are severe, especially the vicious runes on that blade. They're extremely troublesome, and it'll take time to slowly purge the poison. But his will is strong, and his life is no longer in danger." Izuna's voice was tinged with deep concern and a trace of lingering fear, which soon gave way to icy hatred. "Tobirama Senju... He'll pay for this in blood!"

Sou silently nodded. Another link had been added to the chain of hatred.

"Get some rest. The clan won't fail to reward those who've earned their merit." Izuna stood, left some medicine and food, gave the medical ninja a few instructions, and then departed.

Silence returned to the room.

Lying in bed, Uchiha Sou felt his body's weakness and the lingering, needle-like pain in his head. He slowly closed his eyes and examined himself.

Things were worse than he'd imagined. His Chakra pathways were like drought-stricken, cracked earth, and his mental energy was almost completely depleted. The price of forcibly interfering with "Causality" had far exceeded his expectations. Worse still, he could clearly feel that his faint "affinity" with the Natural Energy around him had weakened, as if the world had closed a door that had never been fully open to begin with.

A warning... Was this the will of the world warning and rejecting him because he had tried to forcibly change the fate of an "important person"?

At the same time, though, he had a vague feeling. As he had been drained of everything, hovered on the brink of death, and then been pulled back, he had briefly touched the "essence" of his special ability. It was as if, in absolute nothingness, he had caught a fleeting glimpse of the countless tiny threads that made up "Causality."

He couldn't understand or remember it, but it had left him with an indescribable "intuition."

Just as he had done over the past year, he tried to "resonate" with the fluctuations of "life," as faintly as he could.

It was far more difficult than before, like struggling in solidified cement. The result was negligible; he could barely sense anything at all.

But just as he was about to give up, inspiration suddenly struck him. He stopped trying to "imitate" or "attract" and instead tried to "soothe" the Natural Energy around him, which seemed to regard him with hostility. He did so in a deeply restrained way, almost like a "plea."

Like a child who had broken something precious and was carefully trying to make amends.

Miraculously, the intense feeling of rejection eased, if only a little! His "affinity" hadn't returned, but at least the warning pricking the back of his mind seemed to have temporarily subsided.

He understood. Using this power came at a price and drew the world's vigilance. But perhaps... there was some way to "soothe" or "make amends" to it?

It offered a tiny but important insight into the path ahead.

In the days that followed, Uchiha Sou focused on recovering. The clan provided good resources, and his body slowly healed with the help of his Uchiha constitution and medicine. But he deliberately slowed the recovery of his Chakra and mental energy, making himself appear weaker than he really was to avoid drawing too much attention.

Meanwhile, the clan remained tense and subdued. Madara's severe injuries had temporarily robbed the Uchiha Clan of its sharpest fangs, forcing it into full strategic defense. Izuna shouldered the burden. He grew busier, his eyes sharper and more tired. He had to manage clan affairs and guard against a Senju counterattack while worrying about his brother's injuries.

Details of the ambush were strictly concealed, but word that "Sou warned them at a crucial moment and saved Lord Madara" still spread among a small circle of the clan's upper ranks. His standing in the clan became somewhat complicated as a result, earning him both praise and scrutiny.

Uchiha Sou took it in stride, continuing to keep a low profile.

He spent most of his time in his room, slowly recovering while continuing the "meditation" that seemed meaningless to outsiders—trying to connect with himself and his surroundings through this new approach of "soothing" and "Internal Seeking."

The progress was despairingly slow, but he could feel that every successful act of "soothing" loosened the invisible shackles of rejection a little. His control over the "Causality" within himself also seemed to grow ever so slightly more precise.

Meanwhile, in the Senju Clan Compound.

Under the stimulus of pain, Hashirama Senju's understanding of and ability to merge with Natural Energy deepened. Although he still couldn't maintain Sage Mode for long, he could now deliberately draw Natural Energy into his body, greatly amplifying his ninjutsu and helping his injuries heal. Nourished by his power, the forest continued to spread until it had almost become both a natural barrier and a training ground for the Senju Clan.

The world's "favoritism" was on full display in him.

Tobirama Senju had become a complete workaholic. The death of his assistant Lianglu and the exposure of his unfinished Flying Thunder God Technique had dealt him a heavy blow and only strengthened his obsession. He practically lived in his laboratory, surrounded by piles of calculations and the wreckage of failed experiments. He constantly refined the theory behind the Flying Thunder God Technique and obsessively optimized the failed "Mutually Multiplying Explosive Tags" from that battle, pursuing the greatest possible lethality. His demeanor grew colder, and his eyes held nothing but calculation and destruction.

Now and then, he would think back to the strange deviation of his final attack in the ambush. No matter how he ran the calculations, he couldn't perfectly reproduce what had happened. He was left with a sense of frustration that it had been "no fault of his own." He blamed it on some unknown, bizarre ability of the Mangekyō Sharingan, and his resolve to wipe out the Uchiha grew even stronger.

Time passed, and the border saw a rare spell of genuine calm that lasted for months.

Both sides were licking their deep wounds and gathering strength.

Everyone knew that beneath this calm lay even more terrifying waves, poised to break.

Uchiha Sou's injuries finally healed for the most part, but his strength recovered slowly, and he continued to present himself as an ordinary jonin. He was content with that; it let him hide himself more effectively.

That night, he once again tried to practice "Internal Seeking" at a deeper level.

This time, he no longer focused on "life." Instead, he sank his awareness into the vague impression of the threads of "Causality" he had glimpsed just before losing consciousness.

He tried to "weave" with his mind—not to weave anything external, but to weave the tiny "causes" within himself that represented "recovery," "concentration," and "resilience."

The process was more difficult than any of his previous attempts, and it consumed an enormous amount of mental energy.

Just as he felt he could go on no longer—

Crack!

A tiny sound, as if it came from deep within his soul.

He felt one of the tiny pathways that had been obstructing the free flow of Chakra, congested from overexertion, suddenly clear. His continuous, targeted "weaving" and "setting" had opened it up!

It was only a tiny change, but the results were immediate! His Chakra flowed more smoothly, and his rate of molding it increased noticeably!

He'd done it! For the first time, he had so clearly and deliberately "set" and brought about a tiny instance of "Causality" within himself!

Before the immense joy could well up, that familiar feeling of the world's rejection came again. It was faint, but unmistakable!

Uchiha Sou immediately stopped practicing and began to "soothe" the world instead.

This time, he had a clear goal: to confine the "disturbance" caused by "altering" his own recovery to his body, and to use his thoughts to send the world a message: "This is limited to me" and "I mean no harm."

The feeling of rejection gradually eased, eventually settling into calm.

Uchiha Sou slowly opened his eyes and let out a long breath. Cold sweat had soaked his back.

It was a risk, but it had paid off.

He had found a clearer, yet more dangerous path—to precisely and selectively alter the "Causality" within himself, and pay the price of "soothing" the world.

It was like walking a tightrope over an abyss, but he had no other choice.

He looked out the window. The moonlight was cold.

He knew that once Uchiha Madara's injuries had completely healed, once Tobirama Senju had completed his Forbidden Jutsu, and once Hashirama Senju had fully mastered the power of nature...

A true storm of destruction would descend.

Before then, he had to become strong enough—at the very least, strong enough to struggle to survive in the storm and quietly weave that one thread of "Causality" that belonged to him.

The night was still long, and his path of Fire Stealing had only just begun.