Mangekyo

"They were like the important cities and ports along a river. Chakra was extracted from every cell in the body, initially like countless tiny streams that flowed into these great rivers of the main meridians."

Kosuke raised his index finger and traced a small circle over his body. "Now, setting aside the existing Chakra flow routes, this little circle is the most basic circulation. I call it the 'Lesser Heavenly Circulation.'"

"Listen carefully. It's simple, but extremely important!"

"And you mustn't try it, understand?"

"I don't know what consequences or benefits it might bring. In any case, you must not attempt it before it has been tested!"

Afraid that they might secretly try it, Kosuke had no choice but to solemnly and repeatedly warn them.

Only after seeing everyone nod to show that they understood the severity of the matter did he continue.

He pointed below his navel. "This is the Dantian, where Chakra gathers. Feel it carefully—it's warm."

Kosuke continued moving, turning to point at his spine. "This is the Du Meridian. Chakra begins at the Dantian and flows upward along it, passing through the lower back, the center of the back, and the back of the neck, all the way to the crown of the head."

"This is the Ren Meridian. After reaching the crown, Chakra travels down the front of your body—through the forehead, nose, mouth, throat, chest, and navel—before finally returning to the lower Dantian."

As he spoke, Kosuke traced another circle with his hand. "This circle begins at the lower Dantian, rises up along the back, then comes down the front and returns to the lower Dantian. That is one complete cycle of the 'Lesser Heavenly Circulation.'"

Kosuke paused, picked up his cup, and drained it in one gulp. Then, seeing Izuna and the others desperately closing their eyes and furrowing their brows, he said in a deep voice, "Don't overthink it. There'll be plenty of time to understand it later. Now, let's continue with the 'Greater Heavenly Circulation.'"

At that moment, a ripple suddenly passed through the courtyard barrier.

Aoba shook her groggy head. Her remaining Sharingan instantly activated, and through the courtyard wall, she saw that it was Madara's clone returning from town.

The Earth Clone was carrying an enormous sack over its shoulder, standing outside the barrier and constantly pounding on it.

"How did a barrier get raised here after I was only gone for a while?"

Aoba deactivated her Sharingan, channeled Chakra, and opened a gap in the barrier for the clone to enter.

"Aunt Aoba, has my Earth Clone returned?"

"Yes. It must have found the blank paper Little Kosuke needed."

"Hm? It found it?" Kosuke lowered his hands and looked at "Madara" as he walked into the courtyard, his face lighting up with surprise.

"Help me put it in the room."

At those words, Madara's Earth Clone walked straight past the table in the courtyard and headed toward the room Kosuke had indicated.

"All right, let's continue."

Kosuke's gaze grew deeper. "The Lesser Heavenly Circulation lays the foundation. It manages the circulation inside your 'home.' The Greater Heavenly Circulation connects your 'home'—your body—to the vast world outside!"

Under the bewildered gazes of the others, he suddenly spread his arms wide as if embracing the sky.

"The Greater Heavenly Circulation builds upon a stable Lesser Heavenly Circulation, allowing Chakra to flow from the great rivers of the main meridians into finer tributaries—the tiny meridians spread throughout every limb and bone! More importantly, it opens the body's 'windows' to the outside world—those Chakra Points!"

As he spoke, Kosuke switched the papers in his hands and picked up the diagram that had made everyone dizzy earlier.

His tiny finger kept sliding across it.

"Once our Lesser Heavenly Circulation is stable, Chakra will spread from the Ren and Du Meridians in every direction like tree roots, flowing into your arms, fingers, legs, feet, toes..."

"I speculate that this can greatly improve the precise control of Chakra, allowing it to reach any point in the body as flexibly as an arm."

Aoba's eyelashes trembled slightly as she suddenly thought of the precise control required for Medical Ninjutsu.

"And then..." Kosuke's voice interrupted her thoughts. "The most crucial step is to use specific training and thoughts to try to make those important 'ports' on the surface of your body—your Acupoints—open slightly when you breathe!"

"When you inhale, imagine that you are not merely breathing in air, but also the Natural Energy that exists everywhere in nature. When you exhale, release the 'turbid air' produced by internal circulation from your body."

"What important 'ports' are there?"

Izuna's puzzled voice suddenly rang out.

"You... understood?" Kosuke stopped explaining and looked at Izuna with delight and excitement.

Kosuke's words instantly drew Aoba, Madara, Mina, and the others' attention.

They looked enviously at the hesitant Izuna, unable to stop themselves from muttering inwardly.

Could it be that Izuna had only been pretending before? Was he actually very smart?

However, the thought had barely surfaced before Izuna's next words shattered it completely.

"I... I didn't understand."

"If you didn't understand, then why did you ask?" Kosuke suddenly snapped irritably. He had thought Izuna had understood under his careful instruction.

He had thought Izuna had truly grasped it.

Madara and the others' envious looks immediately turned to disdain.

Kosuke, however, patiently explained, "The most important ones are the Laogong Acupoint in the palms and the Yongquan Acupoint in the soles of the feet."

After casually giving that perfunctory answer, he continued from where he had left off. "This way, Chakra will no longer rely solely on internal extraction. It will become flowing living water: internal circulation nurtures and strengthens the body, while external circulation expels the old and draws in the new, faintly resonating with heaven and earth."

At this point, Kosuke abruptly stopped to add, "Remember, what you absorb is Natural Energy, not Chakra! Something will happen if the two fuse together!"

After saying that, he ignored everyone's reactions and rapidly finished the rest in one breath.

"Your internal energy will recover faster, its quality will become purer, your endurance will grow stronger, and your senses will become sharper! It's like standing in the wind—you won't merely feel the wind, but the power contained within it as well!"

To avoid misleading them, he simply changed the later references to Chakra into energy.

As soon as he finished speaking, Kosuke quickly sat down, poured himself some water, and drank it.

A moment later, everyone's pupils abruptly contracted from overwhelming shock.

"By your reasoning, we can absorb external energy during battle to replenish ourselves too?!"

"Wouldn't that mean we'd only grow stronger the longer we fought?"

Kosuke slowly shook his head. "That's impossible. Haven't you heard of going berserk..."

At that moment, Aoba's expression suddenly became agitated. Her mind recalled her husband's death three years ago, her own willfulness, and Kosuke and Mina's current efforts to become stronger.

Her heart suddenly clenched, and an intense surge of self-blame and grief flooded her mind.

The Three-Tomoe Sharingan abruptly emerged in her eyes and began spinning at high speed.

The afterimages of the tomoe grew increasingly blurred and illusory. At a glance, they seemed to be slowly melting and reforming.

At the same time, Dojutsu began to spread out.

Not understanding what was happening, Mina saw her mother in such grief and wanted to step forward to comfort her.

But Madara, quick-eyed and quick-handed, reached out to stop her.

Sensing the powerful Dojutsu spilling out, he said in a deep voice, "Don't disturb Aunt Aoba!"

Mina turned back to look at Madara in confusion, then shifted her gaze to her younger brother, Kosuke.

Kosuke merely shook his head slightly, signaling her not to disturb their mother. Only then did Mina forcibly suppress her anxiety and quiet down.

If I hadn't willfully taken on that infiltration mission and given birth to Kosuke, would my husband, Uchiha Gen, have survived with my help?

Mina wouldn't be yearning for power this desperately now, either.

With that thought, the special Yin Release Chakra secreted in Aoba's mind grew increasingly dense.

Her rapidly spinning Sharingan suddenly began rotating in reverse.

The three tomoe twisted and melted within the crimson glow, reforming into an exquisite pattern.

Within Aoba's right eye, an inverted blood-red lotus appeared. Chain-like patterns intertwined between its petals, and as Mangekyo Dojutsu surged forth, it bloomed with a red light fierce enough to scorch the soul.

The instant the Mangekyo formed, an invisible pressure descended over the courtyard as tangibly as substance.

Kosuke felt as though an invisible giant hand had clutched his chest. The air around him suddenly froze, and even struggling to breathe became a luxury.

At that moment, the faces of the four children flushed purple, and painful whimpers escaped their throats.

Realizing something was wrong, Aoba swiftly covered her right eye and deactivated the Mangekyo.

The Mangekyo's crimson light flickered through the gaps between her fingers, while the immense Dojutsu receded like the ebbing tide.

Cough, cough, cough, cough—

Kosuke and the others collapsed onto the table, gasping violently and greedily sucking in the sweet air.

After roughly the time it took to drink several cups of tea, Madara, who was two years older, was the first to recover, though he was still breathing heavily.

He straightened his back again, his eyes filled with wild joy as he stared fixedly at Aoba's covered right eye. The envy in his gaze was nearly overflowing.

"Aunt Aoba, your eye..."

Aoba wiped away the blood flowing from the corner of her eye and tried hard to calm the turbulent emotions in her heart.

When she opened her eyes again, the haziness left behind by excessive use had completely vanished, and her vision had become incomparably clear.

Hearing Madara's question, Aoba slowly nodded but did not say anything more.

Only then did Kosuke and Izuna fully escape the suffocating sensation.

Kosuke suddenly grabbed the juice on the table and gulped it down.

"Ha! That hit the spot!"