The new version of internal strength he'd just cooked up didn't deserve a bland label anymore.
"This isn't just basic training," Jinzō muttered, tapping his temple. "This is chakra internal strength I designed myself. Something I can grow in every direction."
He thought for a moment, then smirked."Let's call it… Heavenly Demon Arts. Yeah, that sounds badass."
With that, he raised his palm. Chakra swirled to life, not the usual bright blue — but an inky, jet black.
"Shadow Clone, Substitution, Transformation — no problem. But…" His lips twisted. "Most of my Breathing Techniques and half my Fire Style ninjutsu? Straight into the trash."
What he needed now was a new breathing method that could double as swordplay — one that would actually boost Yin-type ninjutsu. And while most Yin arts were clan-locked secret techniques, as long as they didn't require a bloodline, Jinzō could study and adapt them freely. In fact, fixing his chakra attribute gave him a weird advantage: he could bend those techniques into his own research.
He chuckled. "Though… are people gonna think I'm cheating with Uchiha secrets? Or borrowing tricks from the Nara clan?"
He shook his head. The idea of an "upright Uchiha" tossing around Shadow Imitation Jutsu was ridiculous. He and Shikaku didn't exactly get along, but that wasn't real bad blood. More like… rivalry. The two of them had "similar tastes," and by that, he meant their shared hobby for mature women. A clash of men, not clans.
Still, the thought gave him ideas.
His eyes flicked back to the Sealed Book, landing on a jutsu Tobirama himself had made."The Darkness Technique, huh…" Jinzō rubbed his chin.
Officially, it was classified as genjutsu — but really, it was more like straight-up ninjutsu. Illusions scrambled the brain; Darkness just blanketed the battlefield in absolute black. Unless the caster released it, everyone was stuck blind.
Useless in large-scale fights, sure. But against Uchiha? Brutal. Tobirama had designed it specifically to screw with Sharingan.
Most Uchiha didn't take it seriously. They had blind faith in their eyes, like the Sharingan was invincible until Mangekyō. Jinzō thought they were idiots.
"What if…" he murmured, "I combine Darkness with Shadow Imitation and the Sharingan? Then the darkness I cast isn't just black — it's my world."
And just to top it off, his gaze slid to another page: Flying Thunder God.
That one demanded spatial awareness and sealing skill — both things Jinzō had in spades.
He blew out a slow breath. "One step at a time."
He hadn't even properly started cultivating his Heavenly Demon Arts. The whole idea was to push chakra beyond safe limits — sucking chakra, draining vitality, even leeching blood essence. But that wasn't the kind of thing you rushed unless you wanted to end up as a dried husk.
Step by step. Build the base first.
Knock knock knock.
Jinzō shuffled to the door, dark circles under his eyes from two days of near-sleepless theorizing. He yawned as he pulled it open."Yeah? Who's there?"
On the other side stood Uchiha Yashiro.
"Brother Yashiro?" Jinzō blinked, then let him in. "Didn't expect you today. Come in, sit."
He even set out fruit — a sharp contrast to a certain other Uchiha who always barged into his home without knocking.
Yashiro smiled warmly. "I came to say goodbye. I'm leaving for the Land of Hot Water tomorrow."
Right at the border of Fire Country and Water Country. A war zone.
"Ah, you mentioned wanting to go with Fugaku last time," Jinzō said. He hadn't expected Yashiro to swing by just for farewells.
But Yashiro's gaze lingered on the bags under Jinzō's eyes. The man slipped into his natural role — lecturing like a nagging uncle."You've been pushing too hard. You're young, you need to rest more, pace yourself—"
Jinzō almost nodded off mid-sentence. Yashiro was a good guy, but his "fatherly advice" mode could put anyone to sleep. So Jinzō cut him off fast.
"Brother Yashiro, what's the situation in the Mist these days?"
That got Yashiro frowning. "Kirigakure's… strange. They've been fighting cult ninjas near the Land of Hot Water. Slippery bastards. You never know where they'll strike next. But at least our forward base hasn't been forced into trench warfare yet."
Mist was always a thorn for Uchiha. Their Water Styles countered Uchiha's fire, and their infamous Hidden Mist Technique outright crippled the Sharingan. If anything, the Byakugan was better suited — but Konoha spread the Hyūga too thin, leaving the Uchiha to wrestle with Mist.
"A cult, huh…" Jinzō thought immediately of a certain immortal scythe-wielding lunatic who'd appear years later. "So tell me — do they have that kind of jutsu where you can't die?"
Yashiro shook his head. "Nothing like that. Just… strange, unpredictable techniques. If you don't have intel, even a genin from those cults can kill a jōnin. And some of their 'ordinary' shinobi? They fight like monsters."
Jinzō's eyes narrowed. "Ever heard of the Evil God Cult?"
"Evil God?" Yashiro repeated, shaking his head. "Never heard of it. Probably some tiny sect. But the Land of Hot Water is like that. Small country, but during wars it always churns out bizarre sects and hidden villages. Right now, Tang Hidden Village might even rival Amegakure in influence."
Jinzō leaned back, rubbing his chin. "If you hear anything about them, let me know."
Immortality… if that was real, he wanted it. Badly. Even if he couldn't wield it himself, studying it could change everything.
For now, though, he had to start small. Step one of Heavenly Demon Arts.