Fujin trained for a week. During this time, after Hiruzen ended the training, Fujin would go home and create vacuum cores with his palm while keeping his eyes closed. He did it to become more familiar with the process of creating vacuum cores.

Finally, Fujin managed to create a stable vacuum core inside his mouth. He created a few hand signs and blew out the Vacuum Bullet jutsu.

Unlike Air bullet, where he could blow half a dozen bullets at the same time, he could create just one Vacuum bullet at a time. It travelled in a straight line for 40 meters, piercing everything in its path!

Fujin smiled and exclaimed, 'Damn cool!'

Hiruzen smiled. This time, Fujin performed just as he expected. Of course, his expectations were much higher.

Hiruzen said, "Good work Fujin. You can improve Vacuum bullet jutsu further by creating more vacuum cores so that you can use multiple at the same time. Of course, that won't be easy, so don't push for it so quickly."

Fujin nodded. He needed to use this jutsu a few thousand times. His mastery would improve steadily.

Hiruzen continued, "Other than Vacuum spheres and Vacuum bullets, you can create more vacuum jutsus by changing the shape of the vacuum core. But don't experiment with it for now. Try it after a few months."

Fujin nodded and said, "Thank You, Grandpa."

Hiruzen smiled seeing how obedient he was. However, soon he noticed a slight smile forming on Fujin's face.

Fujin asked, "Grandpa since it is only 9 AM and there is some time for the training session to end, can you teach me how to concentrate chakra in my eyes?"

Hiruzen's eyes twitched! He exclaimed, 'The next time we enter into any negotiations, I should send this shameless brat to negotiate!'

Fujin had analyzed, 'While I'm confident in my chakra control, the eye is a delicate organ. I don't want to damage it. It'd be best if Hiruzen guided me.'

Hiruzen just sighed and agreed. He didn't have anything to do either as Homura was still doing his job.

Hiruzen guided Fujin on how to focus the chakra in his eyes. It needed delicate chakra control but was quite easy for Fujin. After Fujin learnt it, he gave him a few tips and dismissed him. He genuinely was worried that Fujin would ask him for more jutsus.

Fujin knew that he had asked a lot from Hiruzen in the last couple of weeks. So he left after thanking him.

After leaving, Fujin wondered, 'So, what do I do now? Should I rent a training field and practice? I haven't heard from Renjiro at all since Hiruzen took over our training.'

He thought for a bit and left towards the Senju clan compound. He decided, 'Time to redeem that rank A jutsu from Renjiro. Should I ask for anything in particular? I don't really recall any useful Rank A jutsus. Blade of Wind is the only one that comes to mind and I don't need it immediately. I guess I'll just ask him to give me something appropriate.'

Fujin went to the Senju clan compound. However, Renjiro was out on a mission. So Fujin rented a training ground and practiced Vacuum spheres and bullets.

After dismissing Fujin, Hiruzen went back to his office. Seeing Hiruzen enter, Homura became very angry! He said in a grumpy tone, "Hiruzen, you finally remembered to come back?"

Hiruzen shrugged and replied, "The training ended today."

Homura scoffed and replied, "You were teaching 1 jutsu for 16 days? At least say something believable!"

Hiruzen didn't reply. Homura realized that Hiruzen was serious. He asked, "What exactly were you teaching?"

Hiruzen replied, "Well, one of the kids asked me to teach Wind Vacuum jutsus."

Homura's eyes widened. He asked, "And you taught it?"

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Hiruzen nodded.

Homura scolded, "Hiruzen! That jutsu is too dangerous in the hands of a 10-11 year old kid!"

Hiruzen shook his hand dismissing Homura's concern. He replied, "Don't worry. That kid is promising. He is mature enough to not use it on a comrade."

Homura asked, "Which kid is it?"

Hiruzen replied, "Fujin."

Homura burrowed his eyebrows. He asked, "That orphan? I thought you decided on this reward to pacify the Uchiha."

Hiruzen nodded, "I taught her a rank A jutsu. It's a good enough reward. However, I discovered that Fujin is very talented too. He has the potential to be an Elite Jounin. Since he specializes in Wind manipulation, he'd be a very good addition to most of our Jounin teams."

Homura was surprised at the high evaluation given by Hiruzen. He nodded and said, "If the village can get another Elite Jounin, then it's alright. Do you plan to take him into the Anbu?"

Hiruzen nodded, "Yes, but when he reaches 13. We broke the tradition for Itachi due to the situation with the Uchiha. There is no need to break it again with Fujin. Besides, we still need to monitor his performance as a chunin."

Homura nodded. Chunin was a crucial phase in differentiating ordinary ninjas from elites. Many ninjas would get tired of training and stop or slow down their training after becoming chunins. After all, not every ninja could motivate themselves to train all their life. Such ninjas seldom manage to improve their rank. Konoha wouldn't waste any more effort on them.

After 3 days, Renjiro appeared at the training ground Fujin was training in. Fujin, who had just begun his training, sensed him and stopped. Renjiro flickered next to Fujin. He was about to speak when he noticed a bunch of holes in every tree and boulder around Fujin. He was speechless for a moment.

He looked at Fujin and asked, "What did the Hokage teach you?"

Fujin smiled and replied, "He taught me the Wind Vacuum technique."

Fujin extended his arm and fired a Vacuum sphere. Renjiro watched as it pierced through a dozen trees!

He was dumbfounded! He wondered, 'Did he convince that old man to teach him the Wind Vacuum technique and learnt it in under 3 weeks? I knew he was talented at Wind manipulation, but to this extent?'

After the moment of disbelief passed, he felt pride in his student. However, on hearing his student, Renjiro's face immediately became dark.

Fujin asked, "Where were you, sensei? I wanted to ask you to teach me the rank A jutsu!"

Renjiro stared at Fujin, who looked back innocently with a smile on his face. He sighed and asked, "Did you think of any jutsu you want?"

Fujin shook his head and replied, "I'll trust your judgement, Sensei."

Renjiro nodded. Rank A jutsus were hard to find. Rank A jutsu that suited you was even rarer. Fujin did know about a few Rank A jutsu, but most were from other elements. The remaining were very few. So he couldn't decide on what would be the most useful for him.

Renjiro said, "Alright. I have decided to teach you the Shadow Clone Explosion jutsu."

Fujin thanked him, "Thank You Sensei. Can we start learning it now?"

Renjiro was just back from an S rank mission. He had planned to rest, but he agreed.

Renjiro said, "This jutsu has no hand signs. All you have to do is create a Shadow clone and make it self-destruct using all Chakra it has."

Fujin replied, "That's convenient Sensei."

Renjiro nodded and continued, "The advantages are self-explanatory. The limitation is the range. Your clone needs to be very close to the enemy before self-destructing. You will also need to ensure that the enemy doesn't move away quickly on sensing the explosion. As for the disadvantage, since your clone will use all its chakra, you won't be getting any back."

Fujin nodded. It was as he expected. Fujin asked, "So how do we make the clone explode, Sensei?"

Renjiro began explaining the details of the jutsu. Fujin created a couple of Shadow clones and asked them to try as Renjiro explained. Fujin observed them carefully.

After a few minutes, one of the clones exploded successfully! The explosion sent dust flying. After the dust settled, he noticed a small crater where the clone exploded. It had a radius of 2 meters and a maximum depth of 5 cm.

Soon, the 2nd clone exploded as well. Fujin received the memories and experiences of both clones. Fujin began creating more Shadow clones one by one. After one would self-destruct, Fujin would get his experiences and make another Shadow Clone to practice the jutsu.

Fujin's Chakra had increased a lot since the time he received the Shadow clone jutsu! It had multiplied many times. He could now create 21 proper shadow clones that could sustain themselves until they used up two-thirds of their chakra. If he just wanted to create shadow clones for the sake of creating them, he could create 65 Shadow clones!

Of course, these clones won't be able to use a lot of chakra. If he intended to have his shadow clone use Rank B jutsus or supercharged jutsus, then he could only make a few.

[A/N : For those who forgot - I had explained the details when Fujin learnt Shadow Clone jutsu. A Shadow Clone needs a particular amount of chakra to sustain itself. If it didn't have that much, it would be dispelled and the chakra would be returned to the ninja. And a proper Shadow clone would need to be able to use at least 2/3rd chakra before reaching that minimum chakra requirement (basically 3 times the minimum chakra req). Back when Fujin had learnt Shadow clone jutsu for the first time, the minimum required chakra to sustain a shadow clone was 41% of Fujin's entire chakra.]

However, since it was just the purpose of learning how to self-destruct, Fujin created 30 one by one. It emptied 80% of his chakra reserves! However, the progress he made was incredible!