Kakashi looked at his team, face calm and composed, though his mind remained sharp. Naruto, Sasuke, and Sakura were still staring at him, eyes wide, curiosity burning in all three.
"That's enough," Kakashi said, lifting a hand dismissively. "Back to your chakra nature training."
"But Kakashi-sensei-" Naruto began, already mid-whine.
"No buts," Kakashi interrupted smoothly. "You'll understand in time. For now, this isn't something you can handle. Your foundation needs work."
His voice was gentle but firm, leaving no room for debate.
The trio exchanged glances, disappointed but not wanting to argue further. With quiet nods, they returned to their training spots on the grassy field.
Kakashi turned and walked toward the edge of the training grounds. He found a familiar tree, tall, broad, and rooted in the earth like an old guardian, and sank down beneath its shade. Closing his eyes, he inhaled deeply and centered himself.
Beneath his skin, hidden under his clothes, the Chakra Refinement Seal glowed faintly on his abdomen. It pulsed softly, responding to his intent.
The chakra he'd pulled from the Nine-Tails was still inside him.
It wasn't volatile anymore, not dangerous, but it was powerful, dense and heavy, like a compressed storm. He activated the seal carefully, guiding its inner mechanisms to filter the foreign chakra bit by bit.
Time slowed. Minutes passed. Then an hour. Then two.
Kakashi didn't move. He sat perfectly still, sweat beading on his brow, as the seal worked tirelessly to purify the wild energy.
Finally, his eyes opened.
He felt it immediately.
His chakra reserves had grown. The difference was subtle, but it was there, his pool was deeper, richer. His stamina pulsed stronger. Even the natural healing properties in his body had shifted.
His muscles didn't ache. His breath was even, his pulse calm.
"I feel… warmer," he whispered. There was a glow inside him now, not just metaphorical, something alive.
To test the effect, he took out a kunai and made a shallow cut on his forearm. Blood beaded out. For a few seconds, nothing happened. Then, slowly, the wound began to close on its own.
It wasn't instant regeneration, not like Tsunade's or Naruto's, but it was natural healing, greatly accelerated.
"So this is the effect of the Nine-Tails' chakra," he muttered, watching the last trace of blood vanish.
"Even a small amount can do this much?" Kakashi's voice was calm, but inside, he was buzzing.
If he absorbed more… carefully… there was no telling how strong his body could become.
But he shook the thought off. He wouldn't rush it. Not just because it was risky, but out of respect, for Naruto and for the tailed beast sealed inside him.
He could take it by force, but that would cause resentment. Kurama might grow to hate Naruto even more. And Kakashi wouldn't take away his student's greatest hidden strength, not without consent.
No. He would wait.
Standing slowly, Kakashi stretched and walked to a clearing deeper in the woods. Leaves swirled around his feet. Sunlight broke through the trees. He took a deep breath, feeling his chakra respond smoothly.
He was ready.
His thoughts drifted back, to the plot of Boruto: Naruto Next Generation. The young boy named Boruto Uzumaki, Naruto's son. That brat had created something unique.
"A Rasengan… infused with Lightning Release," Kakashi murmured.
He remembered it clearly, the way it disappeared mid-flight. The Vanishing Rasengan. Even the Byakugan couldn't see it.
Boruto had subconsciously mixed his wind chakra with a spark of lightning, giving the Rasengan a unique property. It turned invisible once thrown, striking without warning.
"I can recreate it," Kakashi said to himself. "And maybe even improve it."
He formed a Rasengan in his palm, spinning chakra into a tight, dense sphere. Then, with careful control, he began feeding Lightning Release into it. The sphere crackled softly, its edges shimmering.
The technique was unstable at first, but he refined the mix. Once satisfied, he hurled the Rasengan at a distant tree.
Halfway through its path, the Rasengan vanished.
Then, with a sudden burst, it reappeared, slamming into the tree and exploding with force. Bark scattered in every direction.
"It worked," Kakashi said, watching the tree shake from the impact.
But he wasn't finished. Drawing on his mastery of chakra natures, he layered Wind Release beneath the lightning, shaping the Rasengan into a tighter, faster-spinning orb. The sphere shrank, but its power grew.
He threw it again.
This time, it vanished more quickly, completely gone to the naked eye, before tearing through the tree's bark and detonating inside it. The trunk cracked with a loud snap, splitting halfway through.
"That solves the loss of impact from the vanishing effect," Kakashi thought. "The wind chakra restores cutting power, and lightning masks it from detection."
He raised his hand again and formed another.
This was no ordinary Rasengan. Wind and Lightning danced in harmony.
"This is my Vanishing Rasengan," he said aloud.
A crack of energy echoed across the training grounds.
From a distance, Naruto's head snapped toward the sound. His eyes went wide.
"Whoa! Kakashi-sensei, what was that!?" he shouted, rushing over. Sasuke and Sakura weren't far behind.
Kakashi stood with his glowing Rasengan humming in his hand. "A new variation of Rasengan," he said.
"It looks so cool!" Naruto shouted, eyes sparkling. "Can you teach me!?"
"You've already mastered the first step of Wind Release," Kakashi replied with a small smile. "But this version requires Lightning too."
Naruto's face fell. "So I can't learn it…?"
"Not yet," Kakashi said gently. "You'd need to train or awaken a second chakra nature, Lightning. And even then, you'd need precise chakra control to keep the two natures balanced."
Naruto crossed his arms, sulking. "That's no fair…"
Sasuke stepped closer, eyes locked on the Vanishing Rasengan. "I have lightning," he said simply.
Kakashi gave a slow nod. "You do. And your chakra control has improved. If you train the Wind release chakra, you could handle this jutsu."
Sasuke stared at the spinning orb of energy. The fusion of elements fascinated him. His mind was already breaking it down, analyzing the balance, the rotation, the power.
He turned toward Naruto and smirked.
Naruto saw it. "Sasukeee! What's with that look, huh!?"
Sasuke didn't answer him. He looked back at Kakashi. "I want to try."
Naruto's jaw dropped. "Hey! The Rasengan's my jutsu! Why are you copying me now!?"
"It was the Fourth Hokage's jutsu," Sasuke shot back, his tone cool and slightly smug. "Not yours."
Naruto bristled. "Tch… stupid show-off…"
"Enough," Kakashi said, raising his voice just slightly. "No fighting."
He let the Vanishing Rasengan fade from his palm, the chakra dispersing into the air.
"This version suits Sasuke's chakra nature more than yours, Naruto. That doesn't mean you've failed. You've come a long way."
Naruto looked away, frustrated but silent.
Kakashi stepped closer and placed a hand on Naruto's shoulder. "You're not ready for this one… but in time, I'll teach you something even more powerful."
Naruto looked up, his eyes flickering with interest. "Something better?"
Kakashi nodded. "There's a wind-based variation that's even more destructive. But it's dangerous. It can harm the user if they're not ready."
"You made great progress with your Rasengan. But this version isn't for you yet." Kakashi said. In the future, he planned to tell him how to develop Rasenshuriken. As for now, he can't do it because that jutsu is too violent and may hurt Naruto.
Naruto clenched his fists and nodded. "Okay. I'll get strong enough."
Sasuke stood off to the side, still watching the remnants of the shattered tree.
"Then let's begin soon," Kakashi said to him.
Sasuke nodded.
Sakura, who had been watching silently, finally spoke up. "You've been creating a lot of new techniques lately, sensei. Are you planning to teach us all of them?"
Kakashi gave her a look, one filled with a quiet smile and mystery.
"In time," he said. "Each of you will get what suits you best. My job… is to make sure you survive what's coming."
And with that, he turned toward the tree line once more.