What Is a Technique?

In front of the Merit Recording Office.

A very young ninja walked over. Katsuki recognized him; he was one of Sakumo's subordinates, with excellent strength and talent, already an elite among Chunin.

"Katsuki, Lord Sakumo wants you to come over."

"Mm, okay, I'll be right there."

Katsuki paused for a moment but didn't dare to delay. He quickly responded. Sakumo wouldn't seek him out for idle chit-chat; every time he called for him, it was to teach him something or check his recent training progress.

He turned around and greeted his two teammates.

"Otoha, Tenzan, you guys head back first. I'll be back soon."

"You… you idiot, get lost. Stop showing off in front of me." Otoha rolled his eyes and waved his hands dismissively, like shooing away a fly.

"Hurry up and go, or we'll be so jealous we die…"

Tenzan shook his head with a wry smile.

Inside the main camp, a small training ground had been cleared.

"Attack me."

Sakumo stood in the center of the training ground, beckoning Katsuki.

Katsuki crouched low, his right hand gripping his short sword. He slowly inhaled and exhaled, controlling his body according to Sakumo's teachings. His calf muscles bulged, and he exploded forward like a crossbow bolt, rushing ahead.

His figure flickered, covering ten meters in an instant. The glinting short sword slashed out diagonally, aiming for Sakumo's waist.

"A bit slow!"

Sakumo raised an eyebrow and flicked his left hand forward. His previously pale palm instantly turned iron-gray. With a clang, he blocked the short sword with his bare hand, producing a sound like metal striking granite. It felt as if the short sword had struck not a human body, but a solid piece of granite.

Upon seeing the discolored palm, Katsuki sensed trouble. He immediately retracted his strength. After lightly touching the hand, before Sakumo could make a move, he bent down and rolled away. The short sword in his hand simultaneously swept towards Sakumo's ankles.

Compared to Sakumo's tall frame, he was short. Unless he jumped, he couldn't reach vital areas like the head or neck. However, being short had its advantages; it made attacking the lower body easier, targeting the ankles and knee joints, which could be just as lethal.

As for rolling on the ground, it might not look good… Katsuki didn't care about appearances. Combat was not a performance.

"Sly little thing."

Sakumo shook his head. He channeled power into his feet, instantly leaping off the ground. The short sword grazed past the sole of his shoe, not even touching a single hair. Moreover, Sakumo twisted in mid-air and kicked out, directly hitting Katsuki's backside. Katsuki went flying like a rubber ball.

"Chii!"

The short sword plunged into the sandy soil. Katsuki stopped his rolling momentum, flipped over, got up, pulled out his short sword, and charged again.

He failed repeatedly, but Katsuki didn't get discouraged. It would be truly bizarre if he could injure Sakumo in just a few moves. He and his master had sparred countless times, and each time Katsuki ended up bruised and battered, a truly horrific sight.

However, this small training ground had been requisitioned by Sakumo using his command authority. Besides the two of them, there was no third person. As long as they didn't demolish the training ground, it was difficult for outsiders to perceive anything that happened inside.

Through repeated beatings and Sakumo's meticulous guidance, Katsuki gradually corrected his mistakes, learning how to sever a person's neck, heart, or lungs with minimal energy expenditure.

"You can stop now."

Sakumo suddenly reached out and grabbed Katsuki, who was charging at him, lifting him up like a chick.

"Your progress is excellent. Honestly, it exceeds my initial expectations." Sakumo released the now-calm Katsuki back onto the ground, his gentle smile returning to his face. This made Katsuki's nose sting. Heaven knew that ever since he became Sakumo's student, Sakumo had always had a stern expression towards him.

"Your physical condition is very good. I must say, the Uzumaki Clan is truly astonishing, practically… monstrous."

Watching the bruises and wounds on Katsuki's face slowly fade, Sakumo couldn't help but utter the word. He didn't know that even the Uzumaki Clan couldn't achieve this level; this was the powerful vitality and recovery ability Katsuki gained from developing the Hito Hito no Mi.

"I originally planned for you to train Taijutsu to improve your physical condition as much as possible, and then teach you Ninjutsu in another year. But now, it seems we don't have to wait that long."

Sakumo said with a sigh.

Katsuki's spirits lifted at this. He could finally learn Ninjutsu. As for Sakumo's comments, he just let them go in one ear and out the other.

"Just to confirm, come here." Sakumo took out a square piece of white paper from his pocket and handed it over. It was chakra paper.

Pinching the small sheet of paper between two fingers, Katsuki carefully infused it with chakra. Instantly, the paper shriveled up. When it had shrunk into a crumpled ball, it then, like weathered rock, gradually disintegrated and scattered.

"Hmm, lightning and earth. Very good, very good!" Sakumo nodded, his face full of admiration.

"Katsuki, I have a question for you. What is chakra?" Sakumo pondered for a moment, and instead of teaching Katsuki Ninjutsu, he asked a question.

Katsuki was taken aback. He almost blurted out, 'The power contained within the God Tree's fruit,' but luckily, his mind worked fast enough, and he managed to retract it. After a moment of thought, he carefully answered according to what the clan elders had taught him in his youth: "Chakra is the power source refined by combining the physical energy extracted from cells with the mental energy condensed through training."

"That's correct. Then, another question: What is Ninjutsu?" Sakumo pressed on.

Katsuki's head started to ache. Was this a test? He began racking his brain, trying to figure out how to answer this question.

However, as he truly pondered the question, he was stunned. What exactly was Ninjutsu? Cool special techniques? Lethal weapons? He had never considered such things before. After a long silence, Sakumo wasn't in a hurry. After all, a shadow clone was handling matters outside, giving him plenty of time.

After a long while, Katsuki slowly said, "Ninjutsu is the method of transforming chakra into energy with other properties, and then controlling that energy."

"...Very good. In fact, it's not just Ninjutsu; Genjutsu, Taijutsu, these are all methods of guiding and controlling energy by transforming chakra into more direct, destructive, or deceptive forms. Simply put, it's a way of utilizing chakra." Sakumo stomped lightly, and a mound of earth rose from the ground. He sat directly on it.

"Humans are naturally unable to directly control energies like water and fire. And relying solely on physical strength, apart from those with exceptional talent, humans cannot compare to wild beasts. But with chakra, people can achieve all sorts of incredible things through Ninjutsu, Genjutsu, Taijutsu, and even Secret Techniques and Kekkei Genkai."