In the rear logistics zone of the frontline base camp, a large temporary tent was warmed by the fragrant crackle of charcoal fire, finally driving away the damp chill that had lingered for days.
Fatty pork belly on the wire grill sizzled audibly, filling the space with a mouthwatering aroma.
"Cheers!"
Jiraiya raised his sake dish with a booming laugh, facing the three boys clinking their juice cups across from him. "To Squad Five's first victory—and to sending those Sunagakure puppet-freaks crawling back to their desert! This one's on me!"
"Cheers!" Minato grinned, downing his cup in one go.
Fugaku only sipped his drink with the reserved posture of a proper Uchiha heir, sitting upright, chewing with practiced elegance.
As for Nishikawa Tetsu, his chopsticks were lightning-fast—snatching the largest slice of prime beef right before Minato could grab it.
"I was eyeing that one!" Minato complained.
"If I got it first, your speed's still lacking," Tetsu replied calmly, already chewing. "Besides, brainwork burns calories."
Jiraiya watched the playful squabble with a trace of sentimentality in his eyes.
If only this weren't wartime…
After a few drinks, the stories began to flow.
Jiraiya looked toward Tetsu, who was now poking at Kazama Sōsuke's confiscated puppet scroll, deep in thought.
"Say, Tetsu," he said, rubbing his chin, "Fugaku mentioned you've got a real knack for mechanical puppetry and chemical concoctions. Even invented something you call 'Scientific Ninja Tools,' right?"
Tetsu nodded. "Yes, Jiraiya-sama. I believe chakra shouldn't be used solely for ninjutsu—it's a form of energy that, when combined with physical mechanics and chemistry, can create more stable, reusable tools."
Jiraiya's eyes lit up like he'd just had a stroke of brilliance. "That drive reminds me of one of my teammates. Genius with research, real twisted brilliance. I think you two would hit it off."
He leaned in, grinning conspiratorially.
"How'd you like me to introduce you to Orochimaru once we're back? He's got the best lab resources in the entire village, and he loves sharp kids like you. With his guidance, you'd—"
Tetsu nearly choked on his meat.
Introduce me to Orochimaru?!
His skin crawled. That man was already experimenting on humans, even if no one knew it yet.
I'd be the perfect test subject: smart, orphaned, no clan backing. I'd end up a sample in a jar—or worse, reincarnated via Edo Tensei as a throwaway grunt!
"Cough, cough…!" Tetsu gulped water to calm his nerves and forced out a bright, polite smile. "Thank you, Jiraiya-sama, but I'll have to decline."
"Huh? Why?" Jiraiya frowned. "Sure, he's a little… cold, but the guy's a bona fide genius."
"Well… compared to the cold solitude of a lab, I prefer following a bold, gutsy teacher like you, Jiraiya-sama."
It was a masterfully timed compliment.
Jiraiya burst out laughing, thumping Tetsu's back. "Smart kid! That snake's way too gloomy. You'll go further with me!"
Tetsu breathed a silent sigh of relief.
That was close. Dodged the snake pit by a hair.
With the danger past, Jiraiya turned to Minato.
"Minato."
"Yes, Jiraiya-sensei." Minato straightened immediately, setting his chopsticks aside.
"You did well this time." Jiraiya grew serious. "The training method Tetsu cooked up for you? It's clearly paying off. Your speed is already beyond what most Chūnin can track."
"But…"
He paused, eyes narrowing slightly.
"You still lack a decisive finishing move. Beyond taijutsu and kunai, you don't have a technique that can end a fight against someone with powerful defense. If you'd faced Kazama alone, it would've been rough."
Minato nodded, his expression dimming. "My chakra nature is Wind, but I haven't developed any real Wind Release yet."
"But I've started thinking… I might be better suited for jutsu that don't require hand seals."
"…No hand seals?" Jiraiya raised a brow, putting down his cup.
In the shinobi world, nearly all ninjutsu required hand seals—except for advanced taijutsu and extremely rare shape transformation techniques like the Tailed Beast Ball.
To skip hand seals entirely… that was borderline heretical.
"Yes."
Minato raised his right hand, palm up, eyes glowing with conviction.
"If speed is my strength, even a second spent forming seals is a delay. At high velocity, complicated seals become a handicap."
He paused, gathering his thoughts.
"I was wondering… what if I skipped nature transformation and focused purely on shape transformation? Like the Tailed Beast Ball."
Tetsu almost dropped his chopsticks. This guy… he's really doing it.
He knew what Minato was talking about immediately: the seed of Rasengan.
"The Tailed Beast Ball?!" Fugaku exclaimed, frowning. "You want to compress chakra into your palm? That's only possible for tailed beasts—the chakra density alone would destroy a human's body."
"Not if it's just compression," Tetsu interjected.
Wiping his mouth clean, he continued with a sharp glint in his eyes.
"But what if it's rotational?"
"Rotational?" Minato's eyes lit up. "You mean—?"
"Think of a typhoon," Tetsu said, stirring a cup of water rapidly with his chopsticks until a whirlpool formed. "Pure compression explodes outward. But if chakra spins at chaotic high speeds, you can balance centrifugal and centripetal force to stabilize a dense chakra sphere."
"No elemental change needed. The raw tearing force of compressed chakra would obliterate anything it touches."
Minato watched the spinning water with growing clarity.
"Chaotic spin… spherical stabilization… internal compression…"
His right hand instinctively summoned a faint spiral of chakra. Just a whisper of rotation—but it was the first spark of the Rasengan.
Jiraiya sucked in a sharp breath.
He looked at the two boys before him—one a visionary, the other a conceptual engineer.
"You little monsters," he muttered, shaking his head.
"Do you realize how hard that is? You'd be holding a bomb in your palm. You'll need insane chakra control and natural talent."
"But…"
Jiraiya's gaze settled firmly on Minato.
"…if anyone can pull it off, it's you. And this technique—it would suit you perfectly."
"I'll do my best, sensei!" Minato clenched his fist, eyes ablaze.
"Well, in that case…" Jiraiya grinned, having clearly made a decision.
"Development of shape transformation will take time—maybe a year, maybe two. But in the meantime, we can push your speed even further."
Minato leaned forward. "Even further?"
Tetsu already guessed what was coming.
"Shunshin alone isn't enough."
Jiraiya lowered his voice conspiratorially.
"When I return to the village to report this mission, I'm going to beg the old man to give me access to the Sealed Scroll of Techniques. Inside is the Second Hokage's greatest jutsu—Flying Thunder God Technique."
Minato froze.
Even Fugaku's pupils contracted. As an Uchiha, he understood exactly what kind of jutsu this was.
That was the space-time ninjutsu that killed Uchiha Izuna. The apex of speed.
"It's S-rank space-time ninjutsu," Jiraiya warned. "Incredibly difficult. Dozens have failed to master it."
He looked at Minato again, eyes burning.
"But with your neural response time… I think you might just succeed."
Minato was stunned.
Then a wave of emotion surged within him.
"Jiraiya-sensei…"
"Don't get mushy!" Jiraiya slapped him on the back, nearly knocking him into the grill. "Eat your meat! You'll need the calories if you wanna invent world-shaking jutsu!"
Laughter filled the tent again.
Tetsu watched it all silently.
The theory for Rasengan is in place. The path to Flying Thunder God is open.
The Yellow Flash… is finally on his way.