In the Ninja World, there was a legend of a man born with a rare ability named Jugo.
Jugo possessed a unique body that absorbed natural energy directly, causing him to undergo Sage Transformation involuntarily. However, this ability was too fierce for him to control. Without balance between chakra, physical energy, spiritual energy, and natural energy, he would frequently lose control and rampage uncontrollably.
His good friend Kimimaro once traveled far and wide in search of medical help for Jugo's condition, eventually finding Orochimaru — a shinobi infamous throughout the world. Orochimaru's experiments into forbidden techniques made him curious about the strange power within Jugo, and his research ultimately led him to the mysterious Ryūchi Cave.
In time, the connection between Jugo's abilities and the Snake Sage clan became clearer, and Ryūchi Cave became known as a place of profound serpentine power — on par with the toads of Mount Myōboku and the other great sage regions.
Of course, all of that was in the future.
At this moment, Orochimaru was still buried in his forbidden research and had yet to pursue Senjutsu. Meanwhile, Hayashi, having used Reverse Summoning Technique to arrive ahead of schedule, stood in the yawning darkness of Ryūchi Cave, eyes scanning the shadows as he activated his Sharingan.
Though Ryūchi Cave was indeed a cave, its cavernous halls were vast enough that one could see the ceiling above. The space afforded no sense of suffocation, only unrelenting darkness and bone‑chilling silence.
Hayashi found himself in a central chamber. Towering before him rose a massive rock wall, pocked with hundreds of cave entrances arranged irregularly from low to high. Searching for the White Snake Sage among such an expanse would be like looking for a single scale in an ocean.
Fortunately, Dabai was with him. Unlike the monstrous serpents elsewhere in the cave, Dabai was not built for battle. Instead, she was agile and perceptive — a reconnaissance beast perfectly suited for navigating a labyrinthine environment like this.
She coiled around Hayashi's neck affectionately, then flicked her tongue in the direction of the largest, lowest entrance at the center. With no hesitation, she began leading him forward.
The passageway beyond was pitch black, the only light coming from the faint, white glow radiating from fissures in the rock that grew brighter the deeper they went. The walls widened and curves broadened into open space. Everywhere, countless serpents of all sizes slithered and watched — their eyes reflecting the dim light like flickering red embers.
Because of Dabai, Hayashi regarded snakes as neutral creatures. Their status was roughly equivalent to that of summons far stronger than they appeared — dangerous if threatened, but not to be needlessly attacked.
Yet not all snakes respected that code.
Suddenly, a massive serpent burst from the shadows and blocked their path.
It was Manda.
Manda's face was perpetually twisted into a scowl, his massive fangs bared in disdain. Known as the largest snake in Ryūchi Cave and feared throughout the ninja world, Manda's reputation was as terrifying as his size.
Hayashi stood his ground, unflinching.
"I'm here to see the White Snake Sage," Hayashi said calmly. "I have no time for you. Step aside, or I might regret being polite."
A flicker of malice passed through Manda's reptilian eyes.
"I am not here to injure you," Manda replied in a low voice, "but you are slow. My master has little patience for delay. Climb onto my back — I will take you there faster."
Hayashi eyed Manda skeptically. There was nothing kind‑hearted about the massive snake. Manda had little respect for humans ever since Orochimaru once rejected him in favor of Aoda, a summon with a corrosive nature. It was a matter of pride, and Manda never forgot such slights.
Yet Manda knew that in Ryūchi Cave, only those who dared risk everything could meet the White Snake Sage. Many before Hayashi had entered this place, only to lose their sanity and be devoured by the serpents when they failed to pass the trials.
Seeing no easier way forward, Hayashi climbed onto Manda's broad scales.
The snake propelled them through twisted corridors that branched and forked like a maze. Eventually, they reached a cave entrance that felt unlike the rest — its shape clearly influenced by some ancient architecture rather than bare stone.
Inside, Hayashi's attention was drawn immediately to the enormous statue in front of him. It was a bizarre fusion of serpent and dragon, with an inscrutable expression frozen on its carved face. Clutched within the maw of the statue was a scroll inscribed with the words Ryūchi Cave.
Below the statue, a giant stone dais held the coiled body of the White Snake Sage itself. Unlike a normal snake, this creature was enormous — its white scales gleaming faintly, orange hair flowing across its crown, and yellow, cat‑like pupils that never blinked. Around its neck hung a green cat's eye gemstone, and a red luminescent pearl shimmered atop its head. Thick purple bands adorned its forehead, framed by ox‑horn shaped ornaments — an unmistakable mark of sage power.
Hayashi stood before the serpent, letting out a slow breath.
Golden eyes fixed on him without emotion.
"Child of the Uchiha," the White Snake Sage spoke with a voice that carried oppressive authority rather than warmth, "you have come."
Hayashi met the gaze without flinching.
"You know why I'm here," he said respectfully.
"I know who you are," the White Snake Sage continued, her voice calm and ancient. "When you set foot in this place, it was as if fate itself guided your steps."
Hayashi offered a measured reply. "I seek the Sage Power of Ryūchi Cave."
The White Snake Sage did not sound pleased, but she did not refuse him.
"To learn Senjutsu, one must balance three energies — physical, spiritual, and natural," she explained. "Natural energy exists everywhere, but only a few can sense and gather it. Without balance, a seeker loses themselves and becomes one with the cave forever."
Hayashi nodded.
"I understand the risk," he said without hesitation.
A moment of silence passed before the White Snake Sage's voice echoed softly.
"Child of the Uchiha, listen carefully. You do not need to perform the trials those before you did. You are a contractor of this cave — that alone grants you the right to learn. I will teach you Senjutsu."
Hayashi's eyebrows lifted slightly, but he remained composed.
"Then let us begin."
From a shadowed corner, a small pink serpent slithered forward — her scales soft and gleaming — and hovered beside the White Snake Sage.
"I will instruct you," she said in a gentle voice.
Hayashi looked around, expecting to see the tools or implements used by the Toad Sage at Mount Myōboku — like the legendary toad oil used to attract natural energy — but found none.
The small pink snake, whose name was Tashin‑hime, straightened and explained the next step.
"It is simple," she said, "I will use the bite of my fangs to inject natural energy into your system."
"… Inject natural energy directly into me?" Hayashi echoed, taken aback.
His mind immediately flashed with images of past dangerous trials, and he braced himself.
There were no toad oils, no auxiliary aids, not even the legendary milk used by shinobi masters for healing.
The truth was becoming clear: Ryūchi Cave was not a place of ease, nor was it gentle like the toads. This was a trial by venom and nature itself.
Hayashi sighed lightly.
"If this doesn't work," he murmured, "I suppose I'll have to go find Jiraiya instead."