The training log split diagonal. Clean cut, no resistance.
The two halves fell apart, exposing grain that looked almost polished where the chakra had passed through. Tatsuya stared at his hand, at the faint shimmer of wind-natured energy still clinging to his fingers before it dissipated into morning air.
Months of work. Tsunade's framework, Minato's advice about treating wind and fire as complementary rather than opposing, countless failed attempts that left his chakra channels aching and his patience frayed. All of it condensed into this.
He picked up one of the log halves, turning it to examine the cut surface. The wood fibers were severed cleanly, not torn or crushed. No burning, no splintering. Pure severance.
"That's new."
Minato's voice came from his spot against a tree at the clearing's edge, where he'd been watching with the patient attention he brought to everything worth studying.
"Finished the conversion yesterday." Tatsuya set down the log. "Pure wind-natured chakra shaped with surgical precision. No more layering instability."
"And the cutting power?"
"Haven't tested on armor." He picked up a fallen branch, thick as his forearm, and drew the scalpel across it. The wood parted like water around a blade. "But flesh and bone would sever completely."
Minato pushed off from the tree, rolling his shoulders as he approached. "You sound like you're not sure how to feel about that."
"I'm not." Tatsuya flexed his fingers, feeling the familiar channels where chakra flowed. The technique felt natural now, an extension of the medical emission he'd been refining for over a year. "I spent months developing a tool to cut through anything. Now that I have it, I keep thinking about all the arms I'm going to remove."
"Could be worse. Could be heads."
"That's your reassurance?"
"I'm working with limited material here." Minato's grin was brief but genuine. He crouched to examine the severed log, running his thumb along the cut surface. "The edge geometry is remarkable. This isn't just sharp, it's... there's no resistance at all, is there? The chakra isn't forcing its way through, it's convincing the material to separate."
"More or less. Wind nature at surgical scales behaves differently than battlefield applications. Tsunade was right about that." Tatsuya gathered the log pieces, stacking them with the others he'd been using for practice. "The technique's complete. Now I get to live with having completed it."
Minato was quiet for a moment, watching him work. Then: "Speaking of completion, I've been making progress on a theory. Seal-based spatial manipulation."
Tatsuya raised an eyebrow. "Transportation theory? That's ambitious."
"Jiraiya-sensei's been feeding me texts from the Uzumaki archives. Apparently there were techniques that could fold space entirely." Minato's eyes lit up the way they always did when discussing theory. "The Second Hokage developed one. The Flying Thunder God."
The name hit him sideways.
He knew the Hiraishin — everyone did, at least by reputation. One of the Second Hokage's legendary techniques, lost to impracticality after Tobirama's death. But standing here, watching Minato's eyes bright with theory and ambition, a different kind of knowledge pressed against the back of his skull. This was it. The technique that would make this fourteen-year-old the Yellow Flash. The fastest shinobi who ever lived.
And the man who'd die young, sealing a demon into his newborn son.
"I thought that was lost," he said. His voice came out steady. He wasn't sure how.
"Not lost. Just... impractical." Minato pulled a scroll from his pouch, unrolling it to reveal dense notation that meant nothing to Tatsuya — he could recognize a few structural elements from his reading, but the actual seal work was beyond him entirely. "The original technique works, but the chakra costs are prohibitive for sustained use. Tobirama could manage it because his reserves were monstrous, but even he used it sparingly. For anyone else, it's a desperation move at best."
"And you're trying to fix that."
"I'm trying to understand it first. Kushina's been helping me work through the dimensional folding mathematics, but the anchor seal structure..." He traced a finger along the scroll. "If I can optimize this, reduce the chakra bleed during transit, it stops being a desperation technique. It becomes a combat tool."
"You'd be untouchable."
"I'd be faster than anyone could react to. There's a difference." Minato was smiling now, rolling the scroll back up. "It might take years. Might not work at all. But if it does..."
He trailed off, eyes bright with possibilities he couldn't see the end of.
Tatsuya watched him tuck the scroll back into his pouch. Fourteen years old and chasing a technique that would reshape warfare. The urge to say more pressed against his teeth — be careful, it'll paint a target on your back — but none of that belonged here. Not now, plus Minato is smart enough to at least know that much.
"Then I'd better get faster," he said, "or I'll never keep up."
Minato laughed. "You could try being on time for once."
---
Training Ground Seven looked like a calligraphy shop had exploded.
Brushes of varying sizes lay arranged in neat rows. Ink wells, three different formulations, based on the color variations, sat in a careful grid pattern. Blank scrolls were stacked by size. Practice paper covered every flat surface. And in the middle of it all sat Kushina Uzumaki, her red hair pulled back in a practical knot, her brush moving across a scroll as if she was defusing a explosive tag.
"You're late," she announced without looking up.
"By two minutes."
"Late is late. Sit down, grab a brush, and stop making excuses." The brush didn't pause in its movement, laying down strokes that seemed random until you looked closer and saw the underlying structure. "There's ink prepared on your left. The thin brush, not the thick one. And don't touch the red ink, that's for later."
Tatsuya settled into position across from her, selecting the indicated brush. "What's the red ink for?"
"Mistakes." Now she did look up, and her eyes caught the shift in his expression. "You look different."
"I finished the wind scalpel."
"Ah." The single syllable carried weight. Kushina set down her brush, giving him her full attention for the first time. "First technique you've developed from scratch. Hoorayyy!."
"With significant help."
"Help is how learning works. The creating is still yours." She studied him for a moment longer, then nodded. "Good. Now forget about it. Today we're doing basics."
The lesson that followed was unlike any instruction Tatsuya had received. Kushina didn't teach the way the Academy taught, or the way Tsunade taught, or even the way Minato explained things. She taught the way water wore down stone — constant, patient, and absolutely relentless.
"Storage seals," she said, demonstrating on a practice sheet. "Everyone thinks they understand them. Put chakra here, seal object inside, release chakra there, object comes out. Simple."
"It is simple."
"Wrong." Her brush moved, laying down the basic array. "That's what the seal does. That's not what the seal is. Watch and learn, mister mission report."
She sealed a kunai into the scroll, then released it. Standard procedure. But then she did it again, slower, and this time Tatsuya sensed it — a ripple in the chakra flow, a moment where space itself seemed to fold around the object before it disappeared.
"Sealing isn't about storage," Kushina said. "It's about definition. When you seal an object, you're not putting it elsewhere. You're defining what that space contains. The seal says 'this space contains a kunai' and reality adjusts."
"That sounds like philosophy, not technique."
"That's the foundation everything else is built on." She pushed a blank sheet toward him. "Draw the basic storage array. From memory."
He did. He knew the pattern from his study, even if he'd never successfully executed one. The brush strokes came out rough but recognizable.
Kushina examined his work, whilst nodding her head. "Mhm, technically correct and completely useless."
"What's wrong with it?"
"Nothing's wrong with it. That's the problem." She drew the same array next to his, and even Tatsuya could see the difference. His looked like a diagram. Hers looked like language. "Sealing is communication. You're not just drawing symbols, you're telling reality what you want. Intent matters. Your seal is shouting. Mine is speaking."
"How do I learn to speak instead of shout?"
"Practice. Understanding. And accepting that you'll never be as awesome at this as an Uzumaki, but that doesn't mean you can't be good at it." She grinned, sharp and teasing. "Don't look so offended. You're never going to beat Minato at pure speed either, but that doesn't stop you from learning shunshin."
She was right, and he knew it, which made it more irritating rather than less. "Uzumaki instincts?"
"Close." The deflection was smooth, practiced. "Now. Draw it again. Slower this time. Feel each stroke as communication, not just ink on paper."
He drew. And drew again. And again. Kushina corrected his grip, his speed, his breathing, his chakra flow. By the time Minato arrived with lunch an hour later, Tatsuya's fingers were cramped, his practice sheets were a graveyard of failed attempts, and he'd managed exactly one successful storage seal.
"Progress?" Minato asked, settling down beside Kushina with the casual intimacy of long familiarity.
"Slowwww..." Kushina groaned as she stole a rice ball from his container. "He thinks too much."
"That's usually a compliment in other contexts."
"In sealing, too much thinking gets you blown up." She took a bite, still managing to look imperious while chewing. "Minato learned the hard way. How many eyebrows did you lose that first year?"
"I don't recall the exact number."
"I do. Twelve incidents." She turned back to Tatsuya. "Practice the basic array until you can do it without thinking. Then we'll move to the hard stuff."
Tatsuya looked at his single successful seal, then at the stack of failures. "How long did that take Minato?"
Kushina and Minato exchanged glances. Some silent communication passed between them.
"Three weeks," Minato admitted. "But I had more time to practice."