The Uchiha stronghold never truly slept. Even in the quiet hours of the morning, the crackle of training fires, the clash of sparring blades, and the murmur of strategy sessions kept the halls alive. But tonight, Keiji was not in the courtyard or the barracks. He was walking alone through the elder's wing.
Madara himself had arranged this lesson. "Strength of body you've gained. Power of spirit you've touched. But without the mind, all else crumbles. Go to Elder Gendo. Learn what it means to wield yin."
The name had been enough to stiffen even Izuna's expression. Gendo was not like the other elders. He was older than Tajima, his eyes deeper, his voice rarely heard. A master of genjutsu, feared more than loved, for he could make a man live and die a hundred times in a single blink.
Keiji stopped before the elder's chamber, Gengar floating silently behind him. The sliding door opened on its own.
"Enter."
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The Elder's Lesson
Elder Gendo sat upon a mat, his face carved with lines of age, his Sharingan glimmering faintly in the gloom. Scrolls surrounded him, ink strokes etched with diagrams of eyes, chakra networks, and illusions.
"So," Gendo murmured, his voice dry as parchment, "Madara sends me a child who thinks himself ready to dance in shadows."
Keiji bowed low. "I've come to learn the art of genjutsu."
"Not art," Gendo corrected sharply. "Discipline. Weapon. Poison. Genjutsu is yin incarnate—the power of the mind over flesh. With yin, you can kill without a blade, enslave without chains, and break armies with a whisper."
His eyes locked onto Keiji's. "Tell me, boy—what is yin chakra?"
Keiji hesitated. "It's… the spiritual half of chakra? Imagination, will, thought."
Gendo's lips twitched. "Half-right. Yin is the shadow. It gives form to nothingness. It molds illusion into reality. Without yin, fire burns but cannot frighten. With yin, even the memory of fire can sear flesh. Remember this: yin is not about what is—it is about what the mind believes."
He gestured for Keiji to sit. "Tonight, I will show you three things: control, knowledge, and fear."
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Yin Chakra Control
The first exercise was deceptively simple.
"Close your eyes. Feel your chakra. Separate the warmth of yang—the pulse of muscle, the heat of blood—from the cool of yin—the whisper of thought, the stillness of shadows."
Keiji obeyed, steadying his breath. Inside his body, he felt the storm of energy. Some burned hot, fueling his stamina, his strikes. But beneath it, another current lingered. Cold, quiet, like still water under ice.
"That is yin," Gendo said. "Most Uchiha never learn to separate them. They wield yin clumsily through their eyes, like a man swinging a sword without a hilt. But to master yin is to master silence itself."
Keiji focused, drawing that cold current forward. It resisted, slippery, intangible. Yet with each breath, he caught hold of it, coaxing it to the surface.
His Sharingan flickered. The room around him sharpened, but not in color or motion—in meaning. He could feel Gendo's intent, sense Gengar's amusement even before it chuckled.
"You feel it," Gendo said softly. "Good. Yin is not strength. It is subtlety. With it, you see what others hide, and hide what others cannot see."
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The Weight of Knowledge
When Keiji opened his eyes, scrolls were already spread before him. They spoke of genjutsu arts—the basic False Surroundings, the paralyzing Binding Illusion, the dreaded Demonic Illusion: Shackling Stakes.
"These are tools," Gendo explained, "but they are nothing without knowledge. To craft illusions, you must know what men fear, what they desire. The sharper your mind, the sharper your genjutsu."
He leaned closer. "Tell me, Keiji. What do you fear?"
Keiji froze. His thoughts raced. Death? He had already died once. Loneliness? He had his mother, Madara, even Izuna. Failure? That word struck deeper.
"I fear failing the people who've accepted me."
Gendo's eyes narrowed, studying him. "Good. Remember it. Fear fuels yin. To understand others, you must know your own darkness."
Gengar snickered behind him, and Keiji felt its shadow stir. He frowned but said nothing.
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The First Casting
"Now," Gendo commanded, "cast your first illusion."
Keiji nodded, forming the seals. He gathered yin chakra, let it seep into his Sharingan, and locked eyes with Gendo.
The illusion formed clumsily at first—a flicker of shifting shadows, a faint distortion. But then, something strange happened. Gengar's grin widened. Its aura leaked into him, ghostly cold intertwining with yin. The Eidolon stirred, its spectral current amplifying his intent.
The genjutsu snapped into place.
Suddenly, the chamber was gone. Gendo stood in a wasteland of fire and ash, corpses littering the ground. Shadows rose from the bodies, whispering, clawing. The sky bled crimson, and the air choked with despair.
Keiji gasped. "I didn't—"
Gendo's breath hitched. His Sharingan flared, trying to dispel the illusion—but the genjutsu didn't break. The spectral energy of the Eidolon clung like a second skin, feeding the nightmare.
"Impossible," Gendo rasped, sweat beading his brow. "This is… too strong—"
The shadows lunged, tearing at his limbs. He felt pain, real pain, his body trembling as if the illusion had bled into reality.
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Frightening the Elder
Keiji snapped his hands apart, desperate. "Release!"
The world shattered. The chamber returned. Gendo collapsed to one knee, his face pale, breath ragged. His eyes—eyes that had stared down Senju assassins and wars—trembled with unease.
Keiji stumbled backward, horrified. "I-I didn't mean to! Gengar—my Eidolon—it must have… amplified…"
Gengar floated silently, its grin stretched too wide, its eyes gleaming with something unreadable.
Gendo wiped blood from his lip, staring at Keiji as if seeing him for the first time. "That… was no ordinary genjutsu. Your yin is fused with something else. Something not of this world."
His gaze hardened. "Keiji… even I feared, for a moment. And that should not be possible."
The chamber grew cold. Shadows writhed along the walls, as if Gengar's presence had awakened something deeper.
Keiji's chest tightened. He had come to learn genjutsu, not to terrify one of the Uchiha's most feared elders. Yet now, the air around him felt heavy, dangerous.
Elder Gendo rose slowly, his expression grave. "You are no mere heir of Madara. You are something… else. If you cannot master this power, it will devour you—and perhaps all of us."
Keiji swallowed hard. His hands shook. The thought of losing control terrified him more than the spirits, more than the Senju, more than anything.
And for the first time, he wondered—was his Eidolon gift truly a blessing from system? Or a curse he could never escape from system?
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End of the Chapter
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