Naruto: I start with one door, and I can open it infinitely.

Outside the capital of the Land of Iron.

Lin Chuan and his three companions, along with a samurai, stood here. This samurai would accompany them back to Konoha to explain the mission's upgrade status.

Before leaving, Lin Chuan couldn't help but touch the chakra blade at his waist. Ever since he got it, he had really loved it. It was a perfect fit for his height, and his previous short sword could now be retired.

He had no idea how much the dagger cost. Bai Yunzaojian hadn't mentioned it, and he hadn't asked. It was obvious to anyone that Bai Yunzaojian had probably paid for it himself. Asking further would be asking for trouble and would be impolite.

Since it was the Jonin leading the team's gesture, he silently accepted the chakra blade and silently thanked Hakuyun Hayabusa in his heart. Hakuyun Hayabusa was the first outsider who had been so kind to him, apart from his adoptive parents and Maruboshi Kosuke. Konoha really does have more good people than bad.

As they traveled from the capital of the Land of Iron to Konoha, Lin Chuan kept stroking his chakra blade until it was getting late and they stopped to rest. Only then did he take out the chakra blade and play with it.

This chakra blade is ninety inches long and has a blade two fingers wide. It is lightweight and tough. When chakra is inputted into it, it emits a buzzing sound and the blade is covered with a layer of light blue chakra, which enhances the sharpness of the blade.

This is just the most basic use of the chakra blade. To make the chakra blade sharper, it needs to be imbued with chakra of changing attributes.

For example, Wind Release has the cutting ability, Lightning Release has the sharpness and the ability to paralyze opponents, and other chakra natures also have their own attribute effects.

Unfortunately, his chakra nature is water. Water Release is a form that manipulates water flow, which is effective against Fire Release but weak against Earth Release. Therefore, his chakra nature cannot be used on his chakra blade.

When Shirakumo Hayato got the chakra blade, he taught him how to use it and told him that if he wanted to learn wind-style elemental transformations, he could come to him, as Shirakumo Hayato was a master of wind-style elemental transformations.

Even the techniques for practicing Wind Release chakra nature transformation were explained to him by Hakuun: "Kawa, to make your chakra blade sharper, you need Wind Release chakra nature transformation. You need to divide and polish the chakra, making it thinner through friction, and the sharpness will naturally come out..."

"I understand, Captain Morning," Lin Chuan took out his notebook and wrote down these words. He didn't have time to study now, after all, there were only nine months left until the Chunin Exams, and he still had to learn the Leaf-style swordsmanship, Willow.

It took him three years to learn just one Yin Release attribute transformation, and now he's learning another Wind Release attribute transformation, which is one with low affinity.

It would be difficult to learn in less than three to five years, and with the addition of the S-level sword technique Vacuum Sword, he would need another year to learn it.

In other words, it would take him at least five years to learn the Wind Release: Vacuum Sword technique. In five years, the Fourth Shinobi World War would be over, so what's the point of him learning it?

Even without the Fourth Shinobi World War, it's hard to say whether his body could have lived to the fifth year, so he could only regretfully give up Wind Release Chakra Nature Transformation and Wind Release Vacuum Sword, and learn them next time.

Although he couldn't learn Wind Release: Vacuum Sword, that didn't stop him from memorizing the secrets of Wind Release: Chakra Attribute Transformation and trying it out slowly next time the game restarted...

"Once you've mastered Wind Release: Attribute Transformation, you can come to me to learn Vacuum Sword," Bai Yun said with a slight smile as he saw Lin Chuan's delighted expression. He was glad the child liked it, and offered his first lesson as a teacher.

"I will, Captain Zaojian," Lin Chuan felt that the Vacuum Sword was really cool, but unfortunately he didn't have time. After doing certain things, he couldn't possibly survive Sasuke's defection.

Orochimaru will definitely contact Danzo and have Danzo send someone to kill him. The Root ninjas will definitely keep trying to assassinate him. At that time, he will be unable to defend against the constant assassination attempts, so he will have no choice but to leave the Naruto world he has traveled to.

However, learning all of Maruboshi Kosuke's skills is enough; Shirakumo Zaojian has time to learn the Vacuum Sword technique.

"Ogawa, Captain Hayabusa is really amazing," Tekuno said, pleased that Hayabusa had been taught the Vacuum Sword technique. He thought they could do missions together more often in the future.

"To gain the attention of Hayashima Jonin, this kid is no ordinary person," Hyuga Tokuma poked at the fire with a branch, glancing at Lin Chuan out of the corner of his eye. He hadn't expected that a child who had just become a Genin could gain the attention of Shirakumo Hayashima, which made him pay more attention to him. He could look up information about this kid when he returned to the village.

"I know, Kuno-senpai, Captain Haya is a Jonin," Lin Chuan said seriously. This is a Jonin of Konoha, a well-established Jonin, basically an elite Jonin of Konoha, not a newly promoted Jonin like Kurenai Yuhi.

In the early stages of the Naruto anime, an elite Jonin is already a high-ranking member of a ninja village, with the authority to make suggestions on many matters. Having two Jonin as backers is enough to ensure that his Chunin Exams go smoothly.

……

At the gate of Konoha Village in the Land of Fire.

After two days of travel, traveling light, they finally arrived at Konoha Village on the evening of the second day.

"Phew, I'm finally back," Lin Chuan said, looking at the familiar gates of Konoha Village. He was filled with emotion. The intensity of an A-rank mission was quite high for a newly promoted genin like him.

"Those who want to go home can go home first, and those who don't want to go home can come with me to the Hokage Building. There won't be any more missions for the next two weeks," Bai Yun said, looking at the four people behind him. The samurai would definitely have to go to the Hokage Building with him to report on this S-rank mission.

"I'll go home first," Lin Chuan waved his hand. The reward for this mission had nothing to do with him anymore. His reward wasn't even enough to buy a chakra blade. He knew this perfectly well, so he didn't want to get involved.

"I also want to go home and visit. Call me tomorrow," Hyuga Tokuma said, as a clan ninja, he also needed to report his experiences on this mission to Hyuga Hiashi-sama.

Only Shirakumo Hayato, Tekuno, and a samurai from the Land of Iron remained at the scene. The three of them headed to the Hokage Building together.

"Captain, I can tell you really like this kid. How much did you spend on the knife this time?" Tekuno asked casually as he walked beside Shirakumo Hayato.

"It's not much, just the reward for this mission," Bai Yun said. He took out the reward for this mission and Lin Chuan's reward, and bought Lin Chuan a decent chakra blade. How could his disciple use such a bad ninja tool? That wouldn't be in line with the style of a swordsman.

"Looks like I won't be needed to help," Tekuno had originally wanted to lend a hand, but Shirokumo hadn't asked him to help when she bought the sword that morning, so he missed the chance to help his junior.

"There's plenty of time later. We've arrived at the Hokage Tower." Bai Yun looked up at the Hokage Tower in the morning, stepped inside, and reported the details of the mission to the Third Hokage, Hiruzen Sarutobi.

at the same time--

When Lin Chuan returned home, he was questioned again by his adoptive father and fed until his belly was round and full by his adoptive mother. Only then did he have to wash off the dust and fatigue and lie in his room, staring at the ceiling.

He only had nine months. In order to learn Maruboshi Kosuke's secret swordsmanship, he learned illusion techniques, other swordsmanship, and had experience learning all of Yanagi's prerequisite ninjutsu and swordsmanship.

Next, I should also find Maruboshi Kosuke to learn the Konoha-ryu swordsmanship...

……

The next day, Lin Chuan got up early, ate breakfast, said goodbye to his adoptive parents, and went out to find Maruhoshi Kosuke.

Over the past few years, Maruboshi Kosuke, who had been promoted to Jonin, took on a group of students. These students had graduated three years ago, which is why he thought Maruboshi Kosuke would become the Jonin leading the group.

I don't know if this group of students has graduated yet. As long as a student is promoted from a genin to a chunin, they can team up with others to carry out missions, which can be considered as graduating from the jonin who leads the team.

A group of genin graduating from the ninja academy will generally be promoted to chunin within three years. Only a few, like Shikamaru, are promoted to chunin shortly after graduating from the academy. Even the worst genin will be promoted to chunin within five years. Most of the Konoha 12 are like this.

When he graduated, Kosuke Maruboshi had been teaching this group of students for three years. If Kosuke Maruboshi were to teach students again, he would choose from the graduates of that year. It seems that he was wrong.

Arriving at Maruboshi Kosuke's house, he knocked on the door and opened it, only to see Maruboshi Kosuke practicing boxing in the backyard—the kind of boxing that old people use.

"Ogawa's here. I heard you went on a mission this morning? Did the mission go well?" Maruhoshi Kosuke heard the door open, turned around and saw Hayashi Kawa, and stopped exercising.

"The mission went smoothly," Lin Chuan said, sitting down at the tea table and pouring a glass of water for Maruhoshi Kosuke. He waited for Kosuke to come over before speaking, "Grandpa Kosuke, I've learned the illusion technique Naraku-no-Jutsu. I want to learn your swordsmanship, Willow..."

"Really? It's been three years. You've gotten even stronger. After teaching you swordsmanship, Grandpa has nothing left to teach you," Maruhoshi Kosuke said, taking a sip of water from his teacup and chuckling happily.

"Grandpa Kosuke, my team leader is Hayama-sensei. He taught me Wind Release: Attribute Transformation. Go to him to learn Vacuum Sword," Lin Chuan said, understanding the old man's love of teaching and how he felt when his students had drained him dry, so he could only change the subject.

"Hayama, he's a good young man," said Kosuke Maruboshi, who often teamed up with Hayama Shirakumo and was quite familiar with him. Hayama was a Jonin who was cold on the outside but warm on the inside, and was easy to get along with.

He felt relieved that he was getting old and that a new teacher had taken over to instruct Ogawa. He smiled and explained, "The illusion technique in swordsmanship is a visual illusion. This move is a handprintless illusion released by swinging the sword. It looks like this..."

Maruhoshi Kosuke picked up his short sword and demonstrated to Lin Chuan while explaining, "Illusion magic will make the enemy look like a willow leaf dancing in the wind, binding the enemy so that they cannot move. Then, launch a sudden attack from the enemy's blind spot, pierce through the opponent with one strike, and thus kill the opponent."

"This sword technique is capable of killing an enemy in one strike, and it's also unavoidable unless the enemy's illusionary skills surpass yours. Do you understand...?"

"Grandpa Kosuke, I think I'm under a genjutsu. Please break it, break it!" When Lin Chuan was learning genjutsu, he naturally learned how to break it, which involved disrupting the flow of chakra within his body. However, he found that the effect was not obvious, and his vision was still a little blurry, with double images of people.

"Release it," Maruboshi Kosuke put his hand on Lin Chuan's shoulder and helped him break the illusion of the sword technique Liu. This was an illusion cast by one of his Jonin, and Lin Chuan's ability to remain calm and even try to break the illusion was already quite good.

If it were a normal genin, their body would be contorted at this point, unable to stand, and they would fall to the ground.

"Huff, huff, being under a genjutsu is no fun," Lin Chuan said. He knew the legend that anyone the Sharingan could impregnate with a single glare. The Sharingan's ability to cast genjutsu with just one glare made Kurenai Yuhi's painstakingly practiced genjutsu a joke, leading Kishimoto to ultimately have Kurenai give birth.

"Have some water to calm down, take your time," Maruhoshi Kosuke poured Lin Chuan a glass of water, pointed to the domestic pig in the neighboring yard and laughed, "The pig next door will be your sparring partner from now on. When you can brandish your sword in front of it and make the pig fall down under the illusion, you'll have learned this sword technique..."

"I understand, Grandpa Kosuke," Lin Chuan said after a while, before arriving at the pigpen. He began to wave his knife in front of the pig and simultaneously cast a visual illusion.

He spent the rest of his time learning this sword technique, and even when Bai Yun came to ask him to go on a mission a month later, he refused.

"Captain Hayabusa, I'm currently learning Kosuke's Konoha-ryu swordsmanship, so I can't go on missions. I'm really sorry," Lin Chuan said, having no other choice but to resort to this tactic in the face of Hayabusa's invitation.

"Alright, we'll talk about it after you've learned it," Bai Yun said, seeing Lin Chuan's serious expression. She had no choice but to give up on inviting Lin Chuan and instead turned to invite other ninjas to go on missions.

He also told Lin Chuan to call him if he wanted to do a mission, because without a Jonin to lead the team, Lin Chuan, a Genin, would not be able to accept missions.

In the time that followed, Lin Chuan continued to study swordsmanship. His time was very tight, but then an uninvited guest came to disturb him. This time it was Sasuke.

"Chuan, I went to your house to look for you, but you weren't there. So you were here." Sasuke fell from the tree and saw Lin Chuan swinging his knife at a pig. He didn't understand what Lin Chuan was doing.

"Sasuke? What are you doing here? Shouldn't you be on a mission right now?" Lin Chuan had no choice but to stop studying when he saw Sasuke.

After more than a month of trial and error, he finally grasped a bit of the knack. He believed that it wouldn't be long before he could learn this sword technique, since having a shadow clone to train for him accelerated his cultivation.

"We can only do D-rank missions, it's so boring," Sasuke said as he sat down in the open space under the tree. He saw Lin Chuan pour him a glass of water, so he picked it up, took a sip, and complained about Kakashi, saying that they were treating them like children.

"Kakashi doesn't take on high-difficulty missions? That shouldn't be the case with your strength." Lin Chuan was a little puzzled. With Naruto and Sasuke's current strength, completing a C-rank mission wouldn't be difficult.

"Don't mention it," Sasuke waved his hand lightly. He felt bored whenever Kakashi was mentioned. That guy only knew how to read comic books and left all the chores to the three of them.

"So what brings you here?" Lin Chuan took out a towel to wipe his sweat. Spending all day here wielding his knife was really tiring. He felt like he was back to the miserable life he had endured for the previous nine years.

"I want to awaken the Sharingan, do you have any way to do that?" Sasuke had been struggling with this matter, and finally came to ask Lin Chuan for help. After all, Lin Chuan had always been full of clever ideas since he was a child, and maybe he could come up with a solution.

"Damn, are you really an Uchiha? You're asking me, an outsider, about something like this?" Lin Chuan was speechless. What was this kid thinking, coming to ask him, a non-Uchiha, how to awaken his Sharingan?

Unfortunately, he happened to know how the Uchiha clan awakened their Sharingan. He knew these crazy Uchiha clans better than he knew his own eyes.