A/N:- Sorry for the delay guys. I had an exam to attend, so I was quite busy with the preparation. I did well for the exam and hopefully I will get a good score. I have another exam in a week. I will post two chapters before it and I will skip on exam day.

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"A few centuries ago,

The shinobi world was engulfed in wars and chaos. There were no proper boundaries of the nation. Various clans waged war against each other, either for territory or for resources.

The Senju Clan was one of the most powerful clans. Senju clan enrolled in a battle against the Uchiha clan, another powerful clan.

During those Warring periods, the leader of the Senju clan had five offspring. His elder son was talented in combat.

The youngest son Kenshiro was quite a dunce. He could not master even any basic ninjutsu. In a battle against Uchiha, three of the brothers fell to the Uchiha clan's genius Tenma Uchiha.

Unable to bear the loss of his siblings and to overcome his helplessness, Kenshiro left the Senju clan on a journey to achieve power.

It was during this journey, Kenshiro learned Fuinjutsu. It was during this time, he helped me seal the creature and helped the Shikkotsu Forest."

Katsuyu walks out of the cave and leads Izuna. After walking for a while, they reached in front of a large temple. Katsuyu and Izuna entered the temple.

In the center of the temple, Izuna spot a gigantic statue of a man. The man had long-spiky hairs and a giant scroll is tied to his back. He had two shoulder guards with a Vajra symbol on one of them and a spiral symbol on others. His hands are clasped together, and he is in a battle stance.

"He is Kenshiro Uzumaki! Kenshiro Senju, to be exact. To pay tribute to him, the summons of Shikkotsu forest constructed a temple and erected his statue."

Izuna looks closely at the statue and notices strange marking all over the Statue's body. The markings closely resemble Strength of a Hundred Seal. He turns towards Katsuyu and questions her,

"Isn't that the Strength of a Hundred Seal? That's Tsunade technique right?"

Katsuyu nods to him and reply,

"It is indeed similar to Strength of a Hundred Seal because Tsunade derived her technique from this jutsu. Tsunade's Creation Rebirth Technique is incomplete.

Kenshiro-sama created this technique to use in conjunction with Sage Mode. Mito-sama modified the technique to use Normal Chakra instead of the Sage chakra and Tsunade-sama further improved the technique.

But now her technique has a side-effect. The Original technique created by Kenshiro-sama had strict requirements but it had no side-effects."

"Oh! There was such a thing. Then why don't you help Tsunade-san to learn this original technique." Izuna questions Katsuyu.

"I tried to convince Tsunade-san to learn this technique. But it requires lots of time to learn, and Tsunade-san took part in the Second Shinobi War during her youth, and then the loss of her loved ones caused trauma to her. So, she neglected this technique." Katsuyu sighs.

"I will convince Tsunade to learn this technique. She will heed to my request. You can train Tsunade in this technique." Izuna assures Katsuyu and inspects the temple.

There are various sealing scrolls placed inside the temple. Izuna picks up one of the scrolls and reads it.

"Oh! These scrolls have many sealing techniques written on them. These seals are way beyond the Grandmaster level."

"Izuna-kun! Kenshiro-sama created these seals. He was famous as the 'Sage of Sealing' throughout the Shinobi World. He was a very powerful Shinobi, but sadly he lived a brief life."

Katsuyu sighs and reminisces about her past. Izuna's interest piques and he questions Katsuyu.

"Lady Katsuyu, how did he die? He was a powerful Shinobi, right? Who was capable of killing him?"

Katsuyu looks at Izuna and hesitates for a while before she revealed the fact,

"It was your ancestor, Tenma Uchiha. Tenma Uchiha awakened the power of Mangekyo Sharingan and fought in a battle against Kenshiro-sama. Their battle was intense, Tenma Uchiha had the power of Susanoo whereas Kenshiro-sama had Sage Mode and his various sealing techniques.

Their battle lasted for two days and night. Kenshiro-sama ended the life of Tenma Uchiha. Sadly, Kenshiro-sama succumbed to his injuries from the battle."

'It seems like Kenshiro Senju and Tenma Uchiha were the past incarnations of Asura and Indra Otsutsuki. It is their fate to clash in every incarnation. With Black Zetsu behind the scenes, it is impossible to avoid the battle.'

Izuna inspect the remaining scrolls and remarks,

"Kenshiro Uzumaki had a very high aptitude for Sealing. To gain fame as 'Sage of Sealing' and clash against a Susanoo with Fuinjutsu and Sage Mode alone.

So, after Grandmaster comes the Sage. I hope these scrolls will give me a direction to achieve Sage rank in Fuinjutsu."

He turns towards Katsuyu and asks her,

"Lady Katsuyu, can you help me in training Sage Mode? I want to master Senjutsu and become a Sage."

"Well! I will help you learn Sage Mode, but you have to be compatible with Sage energy to master it. Otherwise, you will turn into stone because of the potent Nature energy."

'Compatibility! I was born with it. I just have to hop in and learn Sage Mode. Later, I will figure out a way to gain 'Six Paths Sage Mode.'

Maybe I should contact with toads and ask that old toad about Hagoromo Otsutsuki. He must have some knowledge about the 'Six Paths Sage Mode'.'

Izuna makes his plan.

"Lady Katsuyu, do you have some sort of aid that helps in the acceleration of the learning process?" He remembers about the Toad oil of the Mount Myoboku.

"We do! It is a slug secretion oil. If you apply it on your body, you can absorb Nature energy faster." Katsuyu leads him to a pool filled with white sticky liquid.

"Ugh! This… "

Izuna looks at the slimy liquid and complains.

"I won't apply it to my body. I will learn the Sage Mode through Normal ways." Izuna complains.

"It is your choice, Izuna-kun."

Katsuyu slithers towards the giant tree in the center of the forest.

"Izuna-kun. The first and the most important thing required to master Sage Mode is a calm mind. If your mind is calm, then only will you able to concentrate on Nature's energy.

Nature energy is present everywhere. Our every breath contains Nature energy. The Chakra system of the body absorbs Nature energy and converts it to Chakra to replenish the Chakra. This way the Chakra System acts as a converter.

But in this, we lose the potency of Nature energy. The Chakra gains an elemental Nature and thus losses its versatility. Nature energy has no elemental Nature which makes it more versatile and potent.

However, there is a catch here. Since it has no elemental nature, it is very hard to sense. And the excessive intake of Nature energy will convert a person to stone, since Nature energy has the will of the planet.

Now, do you have any more questions? If not, then we will start with meditation. Remove all excessive thoughts from your mind and focus on sensing Nature energy."

Katsuyu instructs Izuna and helps him in concentrating.

"Uh! Lady Katsuyu. I used to meditate a lot to calm my nerves. I can easily enter the 'Mind Zero' state. Can we move on to the next stage of the training?"

"… If it is so let's move on to the sensing of Nature energy." Katsuyu looks at Izuna with disbelief. Her Optical tentacles shake frantically.

"Izuna-kun, you have to enter in the meditation state and try to sense the Nature energy around you. You are a sensor type ninja, right? It will be easier for you to sense Nature energy. Just concentrate and feel the Nature energy.

This giant tree releases an enormous amount of Nature energy. It is part of the reason I brought you under this tree. You will be able to sense Nature energy easily here.

But if you are having difficulty in sensing the Nature energy, then you can always apply the slug oil and passively absorb the Nature energy and get a feel of the Nature energy."

Katsuyu points towards the slug oil pool.

"Anything! But that. I will figure out a way to sense Nature energy on my own." Izuna crosses his hand in denial.

"Well! If you say so. I will stay here and monitor your progress. I will prevent you from turning into stone in case you absorb excessive Nature energy." Katsuyu slithers to a nearby boulder and rests against it.

Izuna closes his eyes and enters the mediation state.

'Let me try to feel Nature energy with my body first.'

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Chapter Thoughts:- I have enough material to write complete backstory of Kenshiro Senju, but it would have taken an entire chapter dedicated to it. So, I skipped most of the part. If you want to see the entire story. Just write a paragraph comment in front of it and I will post it.