"You're as despicable as ever, Tobirama."
At the sound of that voice, both Senju Tobirama and Uchiha Sen fell into instinctive alertness, turning toward its source.
There, on the watchtower of the Uchiha encampment in the mountains of Taihang, stood Uchiha Izuna, though none of them had noticed his arrival. His right hand was still poised in the middle of a single-handed seal, the faintest curve of a smile tugging at his lips as his eyes locked onto Tobirama.
"Striking from a place the enemy believes unassailable… that's just like you."
From Izuna's memories, Tobirama shouldn't yet have mastered the Flying Thunder God Technique at this point in history.
But the jutsu he had just displayed left no room for doubt—he had indeed already grasped it.
Not only that, but it was very likely Tobirama had kept it hidden, waiting for this very battle to reveal his trump card.
Tobirama clicked his tongue in annoyance, his expression cold as frost."Speak for yourself. To think you saw through my plan…"
In truth, Tobirama had already perfected the Flying Thunder God months earlier. But he had deliberately withheld it, saving the technique as a secret weapon, biding his time for the moment he could strike a fatal blow against the Uchiha.
The mountains of Taihang had been the Uchiha's unbroken shield for centuries. None had ever breached it.
But that strength bred arrogance. The Uchiha grew overconfident, moving too many of their forces to the front lines, leaving Taihang's defenses thin.
Ordinary shinobi—even those of Kage level—would never be able to slip past so many Uchiha eyes and infiltrate the mountain.
But a sensor of Tobirama's caliber, armed with the Flying Thunder God, could.
From birth he possessed an extraordinary gift for sensing chakra, greater even than his elder brother Hashirama. On the battlefield, he could perceive every shift, every enemy's position, sometimes even the exact number of shinobi in an opposing force.
With just himself, he had launched a surprise strike, shattering the defenses of Uchiha Sen, who had been entrusted with guarding this final stronghold.
Victory had nearly been in his grasp. After securing Taihang, he would have coordinated with Senju Yukuma on the frontlines, with Hashirama, and with the clan's vice-chief—also himself, Tobirama—for a pincer assault from both sides.
If that had succeeded, even if the Uchiha weren't wiped out completely, they would have been crippled, stripped of their ability to contend with the Senju ever again.
But Izuna's sudden appearance had thrown his perfect plan into chaos.
Uchiha Sen's eyes went wide in shock at the sight of him."Izuna-sama! I thought you were still fighting at the front lines!"
"Uncle Sen," Izuna replied coolly as he leapt down from the watchtower, "fall back and see to the wounded. Tend to those who are still breathing."
Sen was of the same generation as Uchiha Tajima, Izuna's father, so Izuna addressed him with respect.
Wiping the blood that ran down his brow, Sen heaved up two still-breathing Uchiha jōnin from the ground."Be careful… that boy's technique is unnatural."
By rights, Sen's skill was equal to Tobirama's—perhaps even superior, thanks to his decades of experience.
But the Flying Thunder God was, without question, a broken technique—one that defied the natural order, capable of felling enemies beyond one's rank.
"…A minor setback," Tobirama muttered as he steadied himself, regaining his composure. His face hardened back into its unreadable mask as he drew fresh kunai, each engraved with the marks of his jutsu. "Once I capture you, I can use you as leverage in negotiations with the Uchiha."
He had fought Izuna before and knew the younger Uchiha's strength. But with the Flying Thunder God in his arsenal, Tobirama was certain there was no possibility of defeat.
Izuna's lips curled into a cold smirk."Big words."
His Sharingan whirled violently, the three tomoe spinning faster and faster—until they twisted into a new shape entirely, three vertical strokes resembling the kanji for "person."
"The Mangekyō Sharingan?!" Tobirama's eyes narrowed in surprise.
Yet he did not falter. With a swift hand seal, chakra surged through his body, and behind him exploded a towering deluge of water, more than twenty meters high—
Water Release: Water Colliding Wave!
The shinobi of the Warring States were on a level far beyond those of later generations. Even the genin of this age were stronger than most of the chūnin in Naruto's time.
"Fire Release: Majestic Destroyer Flame!"
Izuna's hands came together, his lungs filling with air before he unleashed a sea of fire from his mouth, its range no less vast than Tobirama's great wave.
Boom!
The collision of fire and water erupted into a storm of scalding steam and violent shockwaves. Tents of the Uchiha camp were ripped apart, corpses strewn about the ground sent flying.
A pity, Izuna thought grimly. These eyes can still be harvested. Though, in this age, the techniques for transplantation remain crude and undeveloped…
Dark thoughts, yes—but in the Warring States, such pragmatism was ordinary.
Suddenly—Tobirama's chakra signature vanished.
Less than a heartbeat later, he reappeared ten meters above Izuna's head.
The clash of their earlier jutsu had sent many of Tobirama's marked kunai scattering into the air. One had fallen directly overhead, and in that instant, Tobirama had warped to it.
"It's over!" Tobirama roared.
But what he did not know was that, at the very moment he vanished with the Flying Thunder God, Izuna's left Mangekyō had already begun to spin furiously beneath his bangs.
Like a film reel, images unfolded within his eye—
He saw Tobirama vanish, only to reappear above him. He saw the gathering chakra, the signs of a jutsu forming without seals. He saw the attack descending upon his skull.
And then reality caught up.
"Water Release: Heavenly Cry!" Tobirama's voice rang out as he unleashed a torrent of water needles, cascading down like a storm of blades.
Izuna's response was instant. His hand darted to the scroll tied at his thigh, unfurling it with a press of his palm. A barrage of kunai and shuriken burst forth, each tethered to fine, nearly invisible wire.
In the blink of an eye, Izuna seized the wires between his fingers and snapped them taut, whipping the weapons upward.
Whiz! Whiz! Whiz!
The rain of steel met the deluge of water needles, filling the air with a cacophony of clashing metal and bursting droplets before both attacks dissipated into water and scattered shards of iron.
"The Uchiha Shuriken Technique?!" Tobirama's pupils shrank in shock.
What stunned him even more was that Izuna had completely read the trajectory of his attack.
Impossible.
This was Izuna's first time witnessing the Flying Thunder God—how could he already predict it so precisely?!