Shikkotsu Forest

On a high mountain at the border of the Land of Fields, a person suddenly plummeted from the sky. He crashed through two or three tree branches before hitting the ground; although the impact was cushioned, it was clear he was not lightly injured.

This mountain had always been called the Mountain of Evil by the locals. Some said the forest inside was made of white bones, while others claimed the mountain itself could move. Opinions varied, but many who entered never came back out, and over time, no one dared to approach it.

"...Hey... System... did I... make it?"

Indeed, the one who had just fallen was none other than Feng Yao, who had narrowly escaped death. He wasn't sure if the system had played a trick on him.

He had been on the ground when he initiated the teleportation, yet his landing point turned out to be in a tree. After such a long escape, combined with not having eaten...

Feng Yao was already at the end of his rope. He couldn't even grip the trunk and fell straight down, slamming into several thick branches; he estimated he had broken a few ribs.

"Host, you have arrived at Shikkotsu Forest."

But at this moment, Feng Yao no longer had the strength. Upon receiving the news that he was safe, his head grew increasingly fuzzy until he finally slumped over and passed out.

About two or three hours later, a slug with blue stripes on its body crawled out from the ground. It slowly slithered over to Feng Yao's side and examined him carefully.

"How did this human get in here? He looks severely injured. I hope he doesn't die on my turf; it would only attract more people."

With that, it moved its body to crawl onto Feng Yao, and a gentle energy emerged from the small slug, flowing into his body.

The exhaustion and injuries in Feng Yao's body were rapidly recovering. Feng Yao had a dream—a very long dream. He dreamt that after becoming the strongest in the ninja world, he found Earth, returned to China, and lived a happy life with his parents.

"Wah! Huff... huff, did I pass out?"

Feng Yao woke from his dream, tears still lingering at the corners of his eyes. He looked around and was astonished to find that his injuries and fatigue had vanished, but a massive side effect followed.

That's right... he was starving.

Previously, his nerves had been too tightly wound during his escape to care, but now that he had slept and his injuries were healed, his stomach roared like thunder, reminding him it was time to eat.

"Yes, Host. You have been unconscious for eight hours. A slug treated your injuries."

Feng Yao looked around after hearing this, but there was no sign of any slug. However, he couldn't worry about that now; he had to fill his stomach first.

He crawled up from the ground and walked deep into the forest. Along the way, he didn't care if what he found was clean or not—he just shoved whatever was edible into his mouth.

Vegetable leaves, lettuce, lilies...

"This human is truly something... I saved him, and he's still stealing my food."

At this moment, Feng Yao didn't know he had been quietly given a bad review by the Katsuyu Sage. He continued to gorge himself while simultaneously searching for traces of the Katsuyu Sage.

"System, I have one more draw opportunity for completing the mission, right? What can I win?"

Feng Yao asked in his mind while chewing his food. To be honest, given the system's restriction on ninjutsu, he figured it wouldn't let him draw things like that, as the system could just grant them to him directly.

"The lottery system allows the Host to obtain abilities or items from other worlds. It could be an incredibly powerful finishing move, or it could be a toothbrush."

The system's emotionless voice continued to relay information to Feng Yao, causing him to choke on his food. He had always been unlucky with draws; back in China, he only ever got the pity rewards in games.

In the Naruto world, he had drawn Senjutsu, but it was completely unusable. The missions the system gave him were all bizarre, over-leveled challenges. Feng Yao was already traumatized by the draws.

"I feel like I don't even need to draw. You're probably going to give me a toothbrush..."

Feng Yao said irritably.

"Very well, then the Host shall receive a toothbrush."

"No, no... wait! I was joking! Draw, I must draw!"

Feng Yao's change of face was faster than flipping a book. Although he didn't know what he could get, a person had to have dreams... otherwise, how were they any different from a salted fish?

"Understood. Commencing the draw for the Host from the myriad worlds."

Feng Yao swallowed nervously. Less than two minutes later, he heard the system's voice again.

"Congratulations to the Host for obtaining the Six Powers. Do you wish to learn it?"

"Six Powers? That counts as taijutsu, right? If I learn it, can I actually use it?"

Having witnessed the system's infuriating nature, Feng Yao was now terrified.

"Shigan, Rankyaku, Soru, Kami-e, Geppo, and Tekkai are collectively known as the Six Powers in One Piece. They are a form of body technique that pushes human physical limits."

"Please rest assured, Host. This system only restricts ninjutsu and taijutsu within the Naruto world. The taijutsu obtained from the draw is not from this world, so it can be used."

Hearing this, Feng Yao let out a long sigh of relief and waved his hand.

"Learn it, why wouldn't I?"

A massive influx of knowledge surged into his mind, causing a throbbing headache. However, after a short while, Feng Yao realized he had mastered the Six Powers and could use them with ease.

"You damn system, if you had given me this earlier, would I have been beaten so miserably?"

"If the Host could not even handle the previous situation, then the Host would only be a mediocre person. A mediocre person, even with the assistance of this system, could never become the Child of Destiny who transcends this world."

Feng Yao fell silent upon hearing this. It was true; his current strength was nothing compared to the "cheating" protagonists of the later stages. If he didn't grow quickly, he would only be able to watch their backs.

"Geppo!"

Feng Yao instantly exerted force with his legs, moving at high speed. This was a technique that increased movement speed and allowed him to change trajectory while falling through the air. With its help, Feng Yao searched the mountain for the location of Shikkotsu Forest.

After running for about half an hour, halfway up the mountain, Feng Yao discovered a bamboo forest—no, it should be called a bone forest. Aside from a few scattered bamboo stalks, the ground was filled with giant bones standing upright, along with the remains of many animals.

A massive bone tablet was inscribed with the words "Shikkotsu Forest." The bones here were pure white and could be considered very clean, yet Feng Yao still felt a chill run down his spine.

He walked inside, but there was no sign of any slug in this Shikkotsu Forest. He asked curiously:

"System, did you see where the Katsuyu that healed me went?"

"It merged into the ground. Its exact location is unknown."

After silently complaining about the completely irresponsible system, Feng Yao had no choice but to figure things out on his own.

"Katsuyu-sama, I am Feng Yao, a ninja from Konoha. I know it was you who saved me; could you please come out so I may thank you in person for saving my life?"

His voice echoed through the forest, but there was no reply. Feng Yao had no choice but to sit cross-legged on the spot, waiting while he continued to study the Six Powers. A long time passed.

"Since you are already recovered, you should leave quickly. This is not a place you should be, and do not speak of this when you go out."

A voice came from all directions. It sounded very gentle, yet it was clearly an order to leave.

"Damn it, System, didn't you say I had a fortuitous encounter? They're kicking me out—are you even reliable?"

"Host, stay calm. Opportunities must be seized by oneself. Here is a medical text; it is up to you to win them over."

Suddenly, something heavy appeared in Feng Yao's arms. He pulled it out to find the Eastern Medical Canon. Feng Yao's face was a mask of utter confusion.

"What does this mean?"

"Katsuyu Sage specializes in medical ninjutsu and recovery. This medical canon is the crystallization of thousands of years of Chinese history; it holds unimaginable allure for anyone versed in medicine."

Hearing this, Feng Yao understood. Katsuyu had never really appeared in the Naruto series, and knowledge about it was scarce, but among the three great summons, Katsuyu's primary ability was indeed medical.

"Katsuyu-sama, I know you are well-versed in the medical arts. I have a medical book here, a crystallization of thousands of years of wisdom from a powerful nation. I would like to make a trade with you."

As soon as he finished speaking, the ground in front of him began to churn incessantly, and finally, a Katsuyu the size of an adult human emerged.

"A medical book passed down for thousands of years? I recall that no nation in this world has such a history."

Seeing that it had finally appeared, Feng Yao smiled slightly. Appearing meant there was hope. He held the book out.

"Katsuyu-sama will know once you take a look."

Katsuyu took the book with its soft, sticky body. It started by flipping through a few pages tentatively, but as it read on, it became increasingly engrossed and excited.

"Oh! So this can be achieved without medical ninjutsu?"

"It can even be done this way!"

"Does this world have these kinds of herbs?"

Seeing that Katsuyu Sage seemed to have become obsessed with the Eastern Medical Canon, Feng Yao gave a light cough and then, with some effort, snatched it back from Katsuyu's grasp.

"Let me see more..."

"Katsuyu-sama, this book was intended for you, but I have a small request. I wish to learn the Shikkotsu Forest Sage Arts and become a Sage."

Feng Yao dangled the book in front of Katsuyu and made his request with a mischievous glint in his eye. Katsuyu froze upon hearing this. Feng Yao frowned.

"What, is it not possible? Then this book can only..."

"Wait, wait, wait... It's not that it's impossible, but learning Sage Arts is very dangerous. Your chakra is clearly insufficient; you will be directly assimilated by nature."

Hearing this, Feng Yao turned to stone. It was true; he had boosted his chakra once with the system's help, but he still didn't even have half the amount of chakra Naruto possessed. He couldn't withstand the impact of natural energy yet. Just as he was caught in a dilemma:

"Congratulations to the Host for triggering a limited-time reward mission. Granting the reward in advance: Triple Chakra. Mission requirement: Master Sage Mode within one week."

Tagline: As someone who can stand against the protagonist, how can you be looked down upon by a slug? Go and shock the Sage.

"There's such a good thing? Are you still the same system I know? Did you get replaced?"

"The Host is questioning the system, which is equivalent to questioning oneself. Please complete the mission as soon as possible."

As soon as it spoke, the chakra within Feng Yao surged violently. In the blink of an eye, he had reached the minimum requirement for practicing Sage Mode. Even the Katsuyu opposite him was astonished, curious as to why the other party's chakra had suddenly skyrocketed. Facing its questioning gaze:

"Ahem, actually, I was hiding my strength earlier. This is my true chakra level. I believe I have reached the requirements for practicing Sage Mode now, right?"

"Hmm... That is indeed the case. However, I must warn you that practicing Sage Mode is extremely dangerous. Are you sure you want to do this?"

"Yes, I am sure. Please, Katsuyu-sama."

As he spoke, he handed over the book first. Seeing that Feng Yao was so sensible, Katsuyu accepted it and led him into Shikkotsu Forest, speaking as they walked.

"Since you wish to learn the practice of Sage Mode, do you know what Sage Arts are?"

Feng Yao listened to Katsuyu's question and answered fluently.

"So-called Sage Arts involve absorbing natural energy and mixing it in a certain ratio to create Sage Chakra, which allows one to greatly enhance their ninjutsu, taijutsu, and genjutsu, correct?"

"That is correct. For a beginner, the best way to sense the natural energy of my Shikkotsu Forest is to maintain absolute silence in a specific environment, cease all physical activity, and harmonize with nature. I will take you to the sacred ground of my Shikkotsu Forest, where natural energy is most abundant."

After following Katsuyu for about half a cup of tea's time, they finally arrived at a circular structure built from various bones. It was airtight and looked somewhat eerie from the outside.

"These are the remains of once-powerful summons I defeated, fashioned into this Bone House. Inside, you can block out all external interference; neither light nor sound can penetrate it, making it easier for you to sense natural energy."

"Many thanks, Katsuyu-sama. I would like to try it now, if I may?"

Feng Yao could no longer wait. On one hand, he truly wanted to master Sage Mode; on the other, he did not have much time. After receiving Katsuyu's permission, Feng Yao entered the house.

After entering and closing the door, Feng Yao's first sensation was silence—absolute silence. In this pitch-black, airtight space, he could seemingly hear the flow of his blood and the beating of his heart. In the darkness, even the slightest sound of his own breathing was amplified infinitely.

Feng Yao crawled to a sitting position, his hands already faintly sweating. In this completely silent room, it was a form of psychological torture. He tried to sense the energy.

But within a few minutes, he became restless and agitated by the sound of his own heavy heartbeat and breathing. He even felt the urge to rip out his own heart and crush his throat just to make them stop making noise.

Just as Feng Yao was on the verge of collapse, the door opened. Light spilled in.

"Huff... huff... huff... Lord Katsuyu."

By this time, Feng Yao's eyes were bloodshot, and his entire body looked as if he had just been fished out of water.

"Sigh, come out first. This sort of thing cannot be accomplished overnight."

Katsuyu helped Feng Yao out. To be honest, Feng Yao's mental fortitude was already excellent; his psychological resilience was absolutely top-tier, as evidenced by his calm handling of previous battles. Yet, he had collapsed in this room within a short time. Most people, or those with weaker mental states, would likely have fared even worse. Beyond the clever design of the room itself, it was actually imbued with a technique that induced anxiety and unease.

Only by maintaining peace of mind and mental stability under such conditions could one perceive natural energy within Shikkotsu Forest. This was the training method for the Sage Mode of Shikkotsu Forest.

Feng Yao was helped outside and slumped to the ground, asking the Katsuyu Sage beside him.

"Lord Katsuyu, how long was I inside just now?"

While in the room, Feng Yao couldn't even distinguish his own senses; he couldn't feel the passage of time, so he had no idea how long he had stayed.

"About ten minutes. That is already quite good, even exceeding my expectations. It seems you have more talent than I thought."

"Only ten minutes...? Why did it feel like a century to me? How long do I need to persist in there to sense natural energy?"

"According to my estimation, you need to stay in the room... for one day, while remaining conscious."

Hearing this news, Feng Yao stood up immediately and charged back into the room without looking back. What kind of joke was one day? He only had one week in total, and he had only lasted ten minutes. If he didn't risk his life now, he would lose it for real.

Katsuyu watched Feng Yao's figure rush into the house, and after ten minutes, went in again to drag him back out.

"Huff... how was it... did I... last longer?"

Feng Yao was still in the same disheveled state as before.

"About ten seconds longer."

"..."

Thus, Feng Yao rested for a few minutes and dove back in. It went on like this, back and forth, back and forth.

"Keep it up, you can already last twenty minutes now."

Katsuyu said to the bloodshot-eyed Feng Yao while chewing on a leaf.

"You are already approaching an hour now. Have you practiced Sage Mode before?"

Katsuyu asked, looking at Feng Yao who was lying on the ground resting, its mouth dripping with slime.

"Are you a Summoned Beast in disguise? To think you could spend three hours in the Bone House in just two days."

Katsuyu grumbled while dragging Feng Yao out. This had far exceeded the expectations of the Katsuyu Sage.

It was already evening, and Feng Yao's mind was extremely exhausted. His training time over these two days had been incredibly long; he only slept for one hour a night, and even dark circles had formed under his eyes.

"Why are you pushing yourself so hard? You won't die if you don't master the training, but if you train like this, you really will die."

Katsuyu handed over a handful of leaves, while Feng Yao responded silently in his heart: if he didn't master it, he really would die. At his current progress, it was impossible to finish within a week.

"Damn it, System, I knew you didn't have good intentions. Always thinking about harming me. I should have known you weren't that kind! And you suddenly boosted my chakra—I don't care, give me an extension."

"The Host seems to be talking in his sleep. This System's missions are absolute. If the Host cannot complete them, I can only act according to the rules."

"I know! It's just erasure, right... can't you come up with something fresh?"

Thus, Feng Yao could only turn to the Katsuyu Sage for help once more.

"Lord Katsuyu, I don't have much time. May I ask if there are any shortcuts I can take, or any way to speed up my training?"

Katsuyu frowned upon hearing this. To be honest, it had only intended for Feng Yao to try it out so he would realize the difficulty and give up. But seeing Feng Yao so talented and hardworking, it truly wanted to pass the Sage Arts of Shikkotsu Forest to him. It didn't want him to take shortcuts because the danger was immense.

"You should take it slow. If you take a shortcut, the danger will be ten times greater than it is now. With your talent, you will likely master Sage Mode in less than a month; why the rush?"

Katsuyu tried to persuade him earnestly. Feng Yao offered a bitter smile; he knew the creature meant well, but he truly had his own hidden difficulties.

"Lord Katsuyu, I beg you. I must speed up my training. I don't know how to describe it to you, but in short... this is a matter of life and death."

"...Is it really that serious? Hmm... then wait a moment."

Katsuyu pondered for a while as if having made a decision. Suddenly, the entire Shikkotsu Forest—no, the entire mountain range—began to shake violently. Countless rocks and soil fell away as a Katsuyu that seemed magnified countless times crawled out from the mountain. More accurately, the entire mountain was built upon this Katsuyu, and this colossal creature was the true form of the Katsuyu Sage.

The others, including those summoned by Tsunade and Sakura, were merely partial clones of the Katsuyu Sage. Only now did Feng Yao truly feel the power of a Sage; the natural energy in its every gesture was enough to lift a mountain.

"Feng Yao, come here, to my head."

The Katsuyu Sage spoke again. The true form of the Katsuyu Sage exuded an irresistible presence, and Feng Yao obediently ran to the front.

The Katsuyu Sage suddenly spat a glob of slime onto the ground, though it did not appear to be the corrosive kind.

"This is the slime from within my body. Unlike ordinary slime, these are the parts of my body responsible for absorbing and condensing natural energy. After you apply it to your body, you can sense and gather natural energy, and use this to attempt to control it."

"...Slime... is it... thank you, Lord Katsuyu."

To be honest, Feng Yao still felt a bit of psychological resistance toward the slime, but for the sake of the mission and to unlock Sage Mode, he would give it his all!

After collecting the slime, Feng Yao sprinted back to the Bone House, though this time, the Katsuyu Sage sent a clone to follow him inside.

To prevent Feng Yao from being assimilated by the natural energy, it would absorb the natural energy out if necessary.

Upon the first attempt at applying the slime, Feng Yao felt a powerful external energy around his body, and under its guidance, it began to merge into his own. Feng Yao hurriedly urged his own spiritual and physical energy to cooperate in an attempt to fuse with this external natural energy, but after one wave, he was overwhelmed and his entire body was flooded with an excess of natural energy.

His eyes became narrow, two fleshy bumps sprouted on his head, and his body seemed to shrink slightly. The Katsuyu on the side leaped onto him and wiggled, absorbing the natural energy from within Feng Yao's body.

Feng Yao gradually returned to normal, rubbing the skin that had been sucked red by Katsuyu Sage, when he suddenly thought of something.

"Lord Katsuyu, let me absorb natural energy first, but don't absorb it all out. Let me try to fuse the remaining natural energy."

"Hmm~ that method of yours is also feasible. Give it a try."

The man and the slug stayed in this dark house for three days and three nights; aside from occasionally coming out to rest and eat, they didn't even take a break.

"I feel like I'm about to succeed. The fusion of natural energy was just a little bit off before."

"Hmm, I really didn't expect you to master it in such a short time. If only the person who contracted with me had as much talent as you."

"Oh, what happened to her?"

"The first time she entered the Bone House, she was quite emotionally agitated and went berserk within a minute. She even smashed my Bone House before running out."

Katsuyu Sage was most likely talking about Tsunade. Although Tsunade was a medical ninja, her personality was that of an uncompromising strong woman, and she had a fiery temper; making her stay in such a silent environment was undoubtedly a huge torture. It was no wonder she hadn't been able to cultivate the Sage Mode of Shikkotsu Forest.

On the sixth day of training in the Bone House, a subtle yet powerful aura emanated from within. With a loud bang, the gate shattered, and a figure swung a fist, smashing a giant bone standing in the distance into powder.

A youth with snow-white hair, pale blue eyeshadow at the corners of his eyes, and cherry-red eyes stood upon a giant rock. It was Feng Yao, having entered Sage Mode.

His Sage Mode caused a significant change in his physical appearance; his eyes, eyeshadow, and even his hair had turned white. After entering Sage Mode, Feng Yao felt his body brimming with power that had nowhere to vent, which was why he had run out to release some of it.

Looking at the strike before him, Feng Yao was very satisfied.

"Ahhh! What have you done, you brat? Can't you open the door properly? My Bone House!"

Upon hearing this, the majestic aura Feng Yao had just projected instantly collapsed.

"Cough, cough... Lord Katsuyu, don't be angry, don't be angry. I'll fix it for you. I was just a bit too excited earlier."

Hearing the apology, Katsuyu Sage's expression improved significantly. It wasn't truly angry, and seeing that Feng Yao could master the Sage Mode of Shikkotsu Forest, it was actually very happy inside.

Feng Yao sat on the ground, patiently sensing his abilities in Sage Mode. In this state, his mind was exceptionally powerful; it could be said that even in complex matters or extreme situations, he would not feel restless.

At the same time, the natural energy in Sage Mode increased his physical vitality, agility, and defense. He could also use natural energy to increase his sensory range; he could now sense the main body of Katsuyu Sage beneath his feet, which was something he was completely unable to do before.

The most important thing was the process of gathering natural energy. The Sage Mode of Mount Myoboku required standing still for a period of time to gather natural energy, while this Sage Mode of Shikkotsu Forest required even more time to gather it. According to Katsuyu Sage, this time would shorten as he became more proficient.

However, it excelled in duration. The Sage Mode of Mount Myoboku could last for about five minutes, and Naruto relied on Shadow Clones to gather chakra to sustain it, which was decent. But his own Sage Mode could last at least 20 minutes.

In this regard, the combat endurance of the Shikkotsu Forest Sage Mode was far ahead.

Furthermore, he was finally able to experience the power of the System. When he used chakra, the chakra would change its properties according to the Sage Art he intended to use. Now, he had mastered and could use all the Sage Arts that had appeared in Naruto. He opened his hands and formed the hand seals.

Sage Art: Yin Release Lightning Dispatch

This was one of the Yin-Yang Release techniques in Naruto. Under the augmentation of Sage chakra, it could unleash even more terrifying power, allowing his hands to release black lightning to attack enemies.

The black lightning shattered the few remaining giant bones in the vicinity. Even Katsuyu Sage behind him couldn't help but secretly marvel at the power of this Sage Art.

Having tried one move, Feng Yao wasn't satisfied yet; he wanted to try other Sage Arts.

Sage Art: White Rage Technique

Feng Yao's stomach bulged, and he spat out an illusory long dragon. The dragon held a bead in its claws, and the dragon ball emitted a strong light before exploding. This technique could deprive others of their five senses through vibration, damaging their hearing and vision.

Just after using it, Feng Yao discovered that he had been... blinded by his own Sage Art. Fortunately, it was only a minor injury to his corneas, which Katsuyu Sage could help him treat.

While deactivating Sage Mode and sitting obediently to let Katsuyu Sage heal him, he cursed inwardly.

"Damn it, this System really is cheap junk. Do the Sage Arts not distinguish between friend and foe?"

"This is the host's own stupidity; what does it have to do with this System? This kind of Sage Art requires the user to possess certain conditions, and this System only allows you to use all Sage Arts; it won't help you mitigate the side effects."

Feng Yao was speechless. He had indeed been a bit too excited earlier. When Kabuto used this technique, he had used snake corneas to block the intense light. And he... he didn't have any snake corneas.

"Then why didn't you remind me earlier..."

"I thought the host had realized it. Apologies, I still overestimated your intelligence."

The System's infuriating tone angered Feng Yao once again. But fortunately, he had succeeded. In this ninja world, he finally had the means and strength to protect his life.