Fujin celebrated his success in creating a new jutsu within a week by eating in Ichiraku until he couldn't eat anymore. He followed it up by taking a long, well-deserved sleep.

At dawn, Fujin woke up as usual, freshened up and got ready for another day of training. He thought, 'It's been 6 days since the effects of the previous soldier pill ended. My body is rested sufficiently. There shouldn't be any danger in consuming another soldier pill. Let me see how good Hiruzen's pill is.'

Fujin grabbed the bottle that Hiruzen had handed him and moved to the lowest floor in his basement. He opened the bottle and tossed a pill in his mouth. At the same time, the chakra in his body separated into two parts, one having 80% of his chakra and another having 20%.

At the next moment, the entire basement was filled with smoke. 80 Shadow Clones appeared in the basement, each having 1% of Fujin's chakra. Without any word, every clone began working on the Four Symbols Seal. As for Fujin, he left his home and entered the Wind Training room in the Anbu facility.

As he began meditating, he thought, 'I'll skip my physical training when I'm using this chakra pill. While physical training is important, I won't be making any major breakthroughs anytime soon. I can delay it for a bit and use the time to focus on Ninjutsu. Anyways, let's see how effective this pill is.'

Fujin closed his eyes and started his meditation. Two hours later, Fujin opened his eyes. A look of surprise could be seen on his face.

He muttered to himself, 'This pill is incredible. The pill I was using earlier would have needed 10 hours to bring me back to full chakra. But with this pill, I managed to reach it in just slightly over 2 hours! This pill is nearly 5 times as effective!

Such a good pill! I should have asked Hiruzen about this earlier. Once this batch is consumed, I should ask him to procure more for me as well. These are too good. Anyway, it looks like I can train at full strength for at least 80-90 hours in the next 5 days.'

With his chakra back to full, Fujin immediately left the training facility and returned to Training Ground 23. He decided, 'It's time to work on Wind Vacuum Technique. I will first start by creating Vacuum jutsus that don't have to be shot from my mouth. Once I have a sufficient number of them, I will start creating a Vacuum jutsu that can affect a large area.

The first part will also have to be divided into multiple phases. The first phase will involve deciding on a structure of the jutsu and creating it. This should be relatively easier.

The second phase will involve increasing the number of jutsus I can use at the same time as well as using the jutsu in creative ways to catch enemies off guard.

And the last phase will involve granting speed to these jutsus. As long as I can reach the same speed as Vacuum Bullet, then this fighting style will become very difficult to counter.

Anyway, enough planning. Time to convert my ideas into a reality.'

Fujin extended his right arm forward and pointed his finger at a tree. Slowly, a vacuum core, shaped like a bullet, began forming in front of his finger. As soon as the Vacuum Core was formed, it was covered by a multi-layered chakra film and engulfed by winds.

Fujin fired the bullet at a rock. However, mid-route, the bullet collapsed and dispersed into the air. Fujin analyzed, 'Though the concept is similar, I am not used to creating Vacuum Bullet outside my mouth. Still, I should be able to learn this quickly. The difficult part will be travelling speed. It was too slow'

Fujin began practicing creating and firing a Vacuum Bullet with his finger. After a few tries, he managed to make a proper bullet which pierced through the rock. He continued the training as he couldn't do it with 100% accuracy.

A few hours later, Fujin stood at the same spot in the training ground. 3 Shadow clones stood around him, facing in different directions. Each one was facing a different rock. Each rock had hundreds of small holes in them.

At the same time, they pointed at the rocks. Vacuum Bullets began forming in front of their fingers at a quick speed. 1 second later, they fired the bullets at the rocks. The Vacuum Bullets pierced through the rocks and travelled for over a hundred meters, piercing several trees in their paths.

Fujin dispelled his clones and got their experiences. He thought, 'Good. I can now use it without any mistakes all the time. Though the time needed to create it is still high, it should come down as I practice it more. I will begin creating multiple bullets at the same time.'

Fujin extended his right hand forward once again, this time extending all 5 fingers. 5 Vacuum Cores began forming simultaneously, 1 in front of each finger. However, after forming partially, all 5 collapsed.

Fujin sighed and muttered, "Looks like it won't be as easy as I imagined it to be."

He created 3 Shadow Clones and continued his training.

Half an hour later, Fujin sat down with his back against a tree while breathing heavily. He had already dispelled his clones. After catching his breath, a bitter smile appeared on his face. He thought, 'Creating 5 Vacuum Bullets at the same time increased my chakra expenditure by 5 times as well. Using Shadow Clones here isn't very helpful.'

Since his chakra was very low, Fujin returned to the Anbu training facility to meditate for a couple of hours until his chakra recovered.

For the next 4 days, Fujin followed this training plan. He would practice creating Vacuum Bullets with his hands until he ran out of chakra. Once out of chakra, he would go back to Wind Training rooms and meditate for a couple of hours until the soldier pill did its job.

In addition, once every 8 hours, Fujin would dispel the Shadow Clones who were learning the Four Symbols Seal and create new ones. For the first time in his life, Fujin didn't take a single break for 4 days straight. Instead, he considered the meditation time as a break.

As a result, he made rapid progress in two very complex techniques. He could feel that he was getting close to mastering the Four Symbols Seal. And, his control over Vacuum Bullets created outside his body also increased.

And, despite making such rapid gains, no one was aware of Fujin's progress. No one except one person who had rather mixed feelings about the same.

Hiruzen watched in his crystal ball as a few drops of sweat rolled down his face. He swallowed his saliva and wondered, 'Does he have to return to meditate there every time he runs out of chakra? Those Wind Crystals shouldn't even have any more effect on him. It's a complete waste for him to keep using so many of them! In fact, I think he has already consumed more Wind crystals than I consumed Fire crystals!'

As the successor of the mighty Sarutobi clan and Tobirama's student, Hiruzen received abundant help from his clan and the village. So he used a lot of Elemental Crystals. But once the effect of the crystal began reducing, he was made to stop. After all, the Sarutobi clan as well as Konoha had a lot of other ninjas to nurture. Hiruzen understood it and never used an Elemental Crystal after its effect decreased under a certain level.

However, Fujin didn't think about such matters. Unlike a young Hiruzen, Fujin couldn't care less about whether others received Wind Crystals or not. He just focused on becoming strong himself.

Unfortunately, Hiruzen couldn't complain to anyone. He couldn't even ask Fujin to stop using them or use them within limits. After all, ever since the day Fujin stepped into the academy, he had bombarded him with the Will of Fire. Though Fujin was quite mature for his age, Hiruzen wasn't sure how Fujin would take the news of him not being allowed to use any more Wind Crystals.

Hiruzen thought, 'Considering his greedy nature, he will question my Will of Fire if I ask him to limit its usage.'

A bitter smile appeared on Hiruzen's face as he sighed. He muttered, 'Now I see why he agreed for 3 months without any argument. I messed up I should have said 1 month and settled for 1 and a half or 2 months vacation.'

Fujin was blissfully unaware of Hiruzen's sorrow. Of course, even if he knew, he would just grin and continue doing the same. Once his chakra reserves recovered, Fujin returned to the training ground.

He extended both his arms forward and stretched his fingers. In about a quarter of a second, 10 Vacuum Bullets were created. He launched them all at the rock in front of him. The Vacuum Bullets pierced through the rock leaving 10 new holes in it.

Fujin repeated the attack a dozen times until the rock crumbled. Fujin observed the result and analyzed, 'Alright, I can use this attack without any mistakes. The basic form of this jutsu can be considered as mastered. Though I still need a few improvements.'