"If that fish were an enemy ninja, it would have died of old age by now."
Naruto's voice, heavy with exhausted irony, echoed in the silence of the second day of training. Sakura didn't even bother to turn around. She remained kneeling by the same wooden bucket, her forehead covered in sweat despite the morning chill, her eyes red from lack of sleep and extreme concentration.
"Shut up, Naruto!" she snapped, her voice tense with frustration. She was covered in scratches, and her clothes had several small burns from Naruto's explosive failures the day before. "At least I'm not covered in burns! How many times have you blown yourself up this morning?"
"Only three! It's a new record!" he exclaimed with completely misplaced pride from the other side of the clearing, where he sat in the middle of a small, smoking crater. "And I almost got it this time! The sphere was almost... a sphere!"
Sakura sighed, rubbing her eyes. The previous day had been hell. She had managed to make the fish's fin tremble, yes, but Tsunade had raised the difficulty. "Now do it again. And again. Until you can do it with your eyes closed while Naruto is yelling in your ear. A field medic doesn't work in a quiet lab."
"Maybe your problem is theoretical," a calm voice said.
Sakura and Naruto turned. Karin was approaching with Shizune by her side. Unlike them, Karin didn't look exhausted. She looked... centered. There was a calm in her posture that hadn't existed two days ago.
"What do you mean?" Sakura asked, more out of curiosity than irritation.
"Yesterday, Shizune-sensei taught me that chakra flow isn't just about brute force," Karin explained, stopping at a respectful distance from the bucket. "If a cellular network is inactive or damaged, forcing chakra through it only causes an energy rebound. You can't break through the blockage. You have to find an alternate route to bypass it and activate it indirectly."
The explanation was simple, but for Sakura, who had always approached chakra from an academic and logical perspective, it was like a small epiphany. She had been trying to force her chakra into the dead cells, pushing against a wall.
"Alternate routes..." she muttered to herself. "Like the tenketsu points... Theory states that a direct chakra flow can cause a rebound if the cellular network is damaged... but if an indirect flow is used, a kind of bypass..." Suddenly, she looked at Karin with new eyes. "That's... really smart. Thanks, Karin."
"You're welcome," Karin said, a faint blush on her cheeks. It was the first time someone had praised her for her knowledge of chakra, rather than for the amount they could drain from her.
"That's it! You've got it, Sakura-chan!" Naruto shouted, jumping to his feet. "You're the smartest one of all of us! I knew you'd get it! Now make that fish do something, believe it!"
The simple act of sharing a piece of advice and a word of encouragement eased some of the exhaustion from the training. For a moment, they were a team supporting each other.
Many miles away, in the coldest of solitudes, there was no support at all.
The place Kakashi had taken Sasuke to didn't appear on any standard map of Konoha. It was a deep fissure in the earth, a rocky ravine known to the ANBU as "The Silent Fang." Granite walls rose on either side, blocking the sun for most of the day and creating an atmosphere of perpetual twilight. The only sound was the wind whistling between the sharp rocks. It was a place designed for secrecy and destruction.
"Why here?" Sasuke asked, his voice echoing off the stone walls. "Aren't the Uchiha training grounds isolated enough?"
Kakashi, standing in the center of the ravine, didn't look at him. His visible eye was fixed on a huge boulder at the other end. "We need privacy," he answered, his tone devoid of its usual lightness. "And a place where you don't have to worry about holding back. The jutsu you're going to learn isn't subtle."
"Fine," Sasuke said, his impatience obvious. "Then teach it to me. Gaara is my opponent. I need something that can break through his defense."
Kakashi turned slowly. The Hokage's order kept repeating in his mind: "...if you think there is any chance he will choose Orochimaru's path... you must stop him. Permanently." Every word he said, every lesson he taught, felt perilous, as if a single mistake could have fatal consequences.
"Before we start, I want you to answer a question, Sasuke," Kakashi said, his voice serious. "Why do you want this power?"
Sasuke looked at him in disbelief. "Is this a joke? I've already told you. There's a man I have to kill. For that, I need to be the strongest."
"That's a goal, not a purpose," Kakashi replied. "Power that only serves to destroy and get revenge... ends up consuming its owner. It leaves you empty, Sasuke. I've seen it before."
"Save the philosophical sermons, Kakashi," Sasuke spat, his frustration boiling to the surface. "You have no idea what I feel! While you were reading your stupid books, my entire clan was slaughtered by my own brother! Naruto's empathy and Sakura's strength will be useless against him. Or against that monster from the Sand! I need real power. Absolute power. Now, are you going to teach me something useful, or are we just going to waste time?"
Every word from Sasuke confirmed Kakashi's worst fears. He saw the impatience and thirst for power in his student, the same traits he had seen in so many other ninja who had taken the wrong path. And he knew, with a painful resignation, that he couldn't stop him with words. He could only try to give him a tool that he could hopefully control.
"Alright," Kakashi said, his voice barely a whisper. "We'll do it your way."
He raised his right hand. "What I'm about to teach you is my only original jutsu. It's called Chidori. One Thousand Birds."
A sharp, crackling sound filled the ravine. Blue and white lightning materialized in Kakashi's palm, a sphere of chaotic energy contained by the force of his will. The noise was deafening, like the chirping of a thousand birds at once. The light it emitted cast dancing, terrifying shadows on Sasuke's face.
"It's a concentration of Lightning Release chakra in the hand," Kakashi explained over the roar. "A pure assassination jutsu. The principle is simple: concentrate a massive amount of chakra into a point so small it can cut through anything."
With a fluid motion, Kakashi lunged forward. His speed was blinding. Sasuke could barely follow him with his two-tomoe Sharingan. Kakashi thrust his glowing hand into the massive boulder at the end of the ravine.
There was no explosion. There was a cracking sound, and then almost total silence. When Kakashi withdrew his hand, a perfectly circular hole went straight through the rock. The edges were cauterized and smooth.
Sasuke stared at the result, his eyes wide. That was the kind of power he needed. Absolute, undeniable power.
Kakashi walked back, his hand returning to normal. "It has two major drawbacks," he continued, his tone turning stern. "First, it consumes a massive amount of chakra. At your current level, you might be able to use it twice, maybe three times, before you're completely empty. And second, and more importantly, the speed you must move at to use it effectively creates tunnel vision. You charge in a straight line, unable to see a counterattack from the flank."
He pointed to his own left eye. "The only reason I can use it safely is because of this Sharingan. It allows me to perceive an opponent's movements and react, even within the tunnel vision. It's a jutsu that was created, essentially, for a Sharingan user."
Kakashi looked at Sasuke. "I'm going to teach you how to manipulate your chakra to create Lightning. And I'll teach you how to shape it. But I can't give you the chakra reserves or the experience. That's up to you. And I'm warning you, Sasuke. This is a jutsu that tempts you to solve all your problems by charging straight ahead. If you rely on it too much, it will get you killed."
Sasuke didn't hear the warning. He only saw the power. "Let's start."
For the rest of the day, the ravine was filled with the sound of frustration. Kakashi guided Sasuke through the chakra nature manipulation exercises, a task that required immense concentration. Sasuke, a natural genius, picked it up faster than most. Soon, small blue sparks were dancing between his fingers.
But shaping it was another story. His first attempt to contain the power resulted in a discharge that numbed his entire arm, making him drop to his knees with a grunt of pain. The second nearly burned his clothes off. He was learning the hard way that absolute power required absolute control. And as Kakashi watched, every flash of frustration, every look of dark determination in Sasuke's eyes, reminded him that time was running out to complete his terrible mission.
At sunset, back at the Konoha training ground, the mood was one of exhaustion, but not despair.
Sakura, her clothes soaked with sweat and water from the bucket, sat cross-legged. Her eyes were closed, her fingers barely touching the surface of the water. Inside, the fish's tail fin moved with a soft, rhythmic tremor, a motion controlled by Sakura's will. She had progressed from a single twitch to sustained control. She was mentally exhausted, but a quiet smile of satisfaction graced her lips.
Near the stream, Karin held her hands over a small flower whose petals had withered. A faint green light emanated from her palms. Slowly, the wilted petals began to regain their color, to straighten up. It wasn't a resurrection jutsu, but a revitalization at the cellular level, the first real step of the Mystical Palm Technique.
Naruto, for his part, was standing opposite Hinata. He was covered in dirt and bruises from head to toe.
"Ready, Naruto-kun?" she asked, adopting the Gentle Fist fighting stance.
"Whenever you are, Hinata!" he panted.
At Hinata's suggestion, they had changed their training method. Instead of crashing into a rock, Naruto was trying to form the Rasengan with one hand while defending himself from Hinata's gentle yet precise attacks. It was an infernal multitasking exercise.
Hinata lunged at him, her fingers aimed at his chakra points. Naruto dodged, parried, and retreated, all while desperately trying to make the chakra spin in his right hand. The vortex would form, unstable, and then dissipate every time he had to focus on a block.
"Focus on the center!" Hinata advised as they moved.
Naruto listened. In the next exchange, as he dodged a strike, he had a revelation. He stopped trying to control the entire mass of chakra and focused only on the central point of his palm. The wild chakra around it began to swirl around that calm point, drawn to it.
For a second, a perfect and stable sphere, the size of a golf ball, appeared in his hand. It was small, but it was perfect. And he had made it with one hand.
Panting, he dispelled it before he lost control, a huge grin spreading across his face. "I did it! Hinata, did you see it!"
"It was amazing, Naruto-kun," she said, smiling too.
It was then that Shizune arrived, carrying a large basket. "That's enough for today," she announced. "Lady Tsunade says that if you don't eat and rest, your training tomorrow will be useless."
She spread out a blanket and took out rice balls, hot soup in a thermos, and tea. The group gathered, collapsing onto the ground, too tired to speak at first. They passed the food around in a comfortable silence, sharing the simple pleasure of a hot meal after a hellish day of work. The ache in their muscles was a reminder of their effort; the presence of the others was a reminder of why they were doing it.
From the shadow of the trees, Tsunade watched them. She saw Sakura explaining her progress with the fish using hand gestures. She saw Karin eating quietly, not looking over her shoulder for the first time in her life. She saw Hinata and Naruto laughing about something silly. And her expression was a strange mixture of pride and a deep sadness for the conflict she knew was coming.
The sun had completely set in the Silent Fang. The darkness was total, broken only by sporadic flashes of unnatural lightning.
Sasuke stood in the center of the ravine, alone. Kakashi had left an hour ago, leaving him with a final warning: "Don't overdo it. Or you'll burn yourself out."
He had ignored the warning. His body trembled from extreme chakra exhaustion. His right arm hung at his side, numb and covered in burns. But his eyes, the Sharingan spinning frantically in the darkness, were fixed on his hand.
With a scream, he forced out the last of his chakra reserves.
The lightning exploded around his hand, far more wild and chaotic than Kakashi's controlled version. It was not a contained sphere. It was a mass of crackling, unstable, and savage energy. And the sound... was unmistakable. The sharp, piercing chirp of a thousand birds, a sound of assassination that shattered the silence of the night.