Yo's body shuddered.
He felt a cold, violent energy unlike chakra explode directly inside him.
This energy brimmed with vitality, yet carried an overbearing force that sought to assimilate everything into itself.
Yo's skin turned pale and bloodless, like that of a cold-blooded animal.
Beneath his skin, white snake scales burst through the surface.
At the same time, his body began to swell and twist uncontrollably, as if transforming into some kind of serpent.
More terrifying still, the skin on his feet lost its elasticity and color, turning into lifeless gray-white stone.
Petrification... had begun!
Natural Energy was rapidly eroding his body, trying to turn him into one of Ryūchi Cave's countless stone statues!
"Just as I thought... it's overbearing!"
Yo immediately focused his entire mind, relying on the terrifying chakra control he had honed over many years.
He began to catch and guide the strand of Natural Energy running wild inside him.
The process was extremely difficult!
Natural Energy was like a wild horse that had broken free of its reins, unruly and incompatible with his mental and physical energies.
The snake scales continued to spread across his skin, while the petrification had already crept from his calves to his knees.
Yo didn't flinch. He drew on his mental energy and cellular energy, using them as a binder to envelop the strand of Natural Energy.
Guidance, resonance, fusion!
Fortunately, the strand of Natural Energy was tiny. With Yo's effort, it was soon tamed and fused.
At last, it blended perfectly with his mental and physical energies in the ideal ratio of 1:1:1.
A wisp of a new energy came into being in the pathways of Yo's body.
Though it was only a wisp, it contained terrifying power far beyond chakra. It was Senjutsu Chakra!
The instant that wisp of Senjutsu Chakra formed, the changes across Yo's body abruptly stopped!
The spreading snake scales ceased growing and slowly receded.
The stone covering his legs up to his knees receded like a tide, restoring the softness and sensation of flesh.
Yo slowly opened his eyes and let out a long breath. The process had been perilous and exhausting, but he had succeeded.
He had mastered his first wisp of Natural Energy and fused it into his first wisp of Senjutsu Chakra.
The White Snake Sage watched in silence, her amber eyes unruffled, as if she had foreseen this result all along.
"Excellent control and resolve! You truly are a genius!"
The White Snake Sage's aged voice rang out. "Now, you must learn how to sense and absorb the Natural Energy around you on your own, and maintain it steadily!"
Successfully controlling Natural Energy and forming his first wisp of Senjutsu Chakra
meant Yo had qualified to train in Ryūchi Cave Sage Mode.
It also offered initial proof that he had the potential to control Natural Energy.
According to Ryūchi Cave's rules,
he could stay here and receive guidance from the White Snake Sage or Ryūchi Cave's senior members as he learned Sage Mode.
For anyone yearning for power, this was a once-in-a-lifetime opportunity, and Yo was eager to seize it.
The tremendous boost from Sage Mode was vital to improving his strength.
He was determined to master Ryūchi Cave Sage Mode as quickly as possible.
However.
Just then.
Whoosh!
A strange stream of information suddenly flooded his mind. It had been sent by the Shadow Clone he'd left in Konoha:
Uchiha Itachi and Kisame Hoshigaki had appeared in Konoha! He needed to return immediately!
Itachi had finally arrived!
Yo's spirits lifted. He immediately turned to the White Snake Sage on the platform. "White Snake Sage, I'm terribly sorry!"
"There's an urgent matter in Konoha, and I have to return to deal with it!"
"Could I put off my senjutsu training for the time being?"
The White Snake Sage wasn't surprised by Yo's sudden request.
"You've earned the right to learn Ryūchi Cave Sage Arts. When you train is up to you!"
"Thank you!"
Yo performed the Reverse Summoning Technique and vanished from Ryūchi Cave.
Outside Konoha, on the river by the edge of the woods, tension hung in the air.
Asuma supported the injured Kurenai Yuhi as they slowly retreated, both of them tense and wary.
Kakashi stood in front of them, staring intently at the two figures before him.
Two men in Black and Red Cloud Robes stood before them: Uchiha Itachi and Kisame Hoshigaki.
"Kakashi-senpai!"
Uchiha Itachi's voice was calm, his expression impassive.
"I'm not like Kisame. I won't waste much time!"
Before he had even finished speaking, the three tomoe in his scarlet eyes began spinning faster, joining and transforming!
They formed a three-pointed pinwheel pattern—the Mangekyō Sharingan unique to Itachi.
The instant Kakashi met his gaze, his body shuddered, as if struck in the head by an invisible hammer.
He froze for a moment, then toppled backward without warning.
Dropping to one knee, he braced himself with one hand and gasped for breath, his forehead instantly beaded with cold sweat.
His eyes were unfocused, his face still twisted with pain and shock.
It was as if, in that brief instant, he had endured countless horrific deaths and tortures.
"Kakashi!"
Asuma cried out.
"Mr. Itachi... is this the power of your eyes?"
Kisame Hoshigaki grinned, baring his sharklike fangs.
"Then let's take care of the Copy Ninja while we have the chance!"
Kisame stepped forward and unwound Samehada's bandages. The barbs along the blade sprang upright, aimed at Kakashi, who had nearly lost the ability to fight back.
"Teacher Kakashi, you look like you could use some help!"
A calm voice suddenly came from the woods to the side.
It wasn't loud, but it drew everyone's attention.
They looked toward the sound. A figure had appeared on the branch of a nearby tree without anyone noticing.
He was a black-haired boy wearing an ordinary dark shinobi uniform, his hands casually tucked into his pockets.
Sunlight filtered through the leaves, casting dappled shadows over him.
"Yo!!"
Kakashi managed to lift his head. When he saw Yo, he finally relaxed completely, his body going limp as he collapsed.
Whoosh!
Yo suddenly appeared beside Kakashi and reached out to support him. "Teacher Kakashi, are you all right?"
"I'm... fine!" Kakashi replied weakly.
Asuma and Kurenai Yuhi's taut nerves relaxed all at once.
Reinforcements had arrived!
They had all seen Yo's strength for themselves. Now that he was here, today's situation would surely be resolved.
Uchiha Itachi's pupils contracted almost imperceptibly. At last, the expression he had kept unchanged for years flickered ever so slightly, and his heart stirred.
It was Yo... He had... He had grown so much!
Itachi gazed silently at Yo, as if trying to etch him into his memory.
But his expression remained cold and unchanged.
Kisame Hoshigaki had noticed Yo too. He tilted his head toward Itachi and asked with a hint of amusement:
"Hey, Mr. Itachi, that kid's got red eyes just like yours. Could he be your little brother?"
"He is my younger brother," Itachi said evenly.
"So he really is your brother?"
Kisame sounded intrigued.
Yo lifted his head and looked at Uchiha Itachi, the most unfilial son of all.
Unlike Sasuke, whose hatred ran bone-deep,
Yo showed no sign of deep-seated bitterness. He didn't even seem particularly angry as he calmly looked at Itachi.
"Long time no see, Itachi!"
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