Standing in the back yard of their house, Chiba and Koizumi we're sparing as two clones lay nearby with paintbrush and paper in hands. It had been over a week since he got back to the village and he was already scheduled to return to the front lines tomorrow.
Chiba had never wrote a single letter of kanji in his past life, and Fuinjutsu required having incredible Kanji writing as the bare requirement to begin. Thankfully, having a superhuman body made him a lot more dexterous and allowed him to quickly get better and better at writing.
Slashing forward horizontally Koizumi, who had her Sharingan activated, used the attack as a feint in order to sweep Chiba's legs out from beneath him, only for the moment she lifted her leg up, Chiba legs swooped in and kicked her sole leg out from beneath her.
"You're merely copying my moves verbatim with obvious wind ups, this won't be a problem when face a new weak opponent but once you encounter an enemy that has seen you before or can analyze your style mid combat, then they might as be able to see the future with how predictable you are! Again!"
Standing up, Koizumi launched her herself at Chiba once again just as one of his shadow clone finally felt like he had achieved good enough writing to finally start training his Fuinjutsu.
When Chiba wasn't training with Koizumi, he was spending his time with his two shadow clones practicing Kanji.
Kushina gave Chiba her promise that she will not hold back on him, she'll let him learn any and all of the Fuinjutsu that she knew. In exchange, Chiba was to help Minato bridge the gap in the village and Uchiha, which was the number one domestic conflict in Konoha.
Chiba had a feeling that there was more to her wanting him to become her disciple, if he had to guess it had to do with the Nine tailed fox fearing his Observation Haki. He assumed she wanted to build him up as a line of defense against the Kyubi.
He didnt mind her reasonings seeing as how this alligned perfectly with Chiba's wishes, he chose to become Kushina's disciple as he started brainstorming ideas to use fuinjutsu.
Chiba knew that his template abilities alone are at the kage level when it comes to attack potency, but he was still stuck with a normal body of this world. His template didn't increase his chakra levels and he knew he was only slight above average as he was an Uchiha.
Fuinjutsu was exactly what Chiba needed to become stronger as he already knew a couple of ways to increase his chakra with it, he just needed to reach a good enough level at the Fuinjutsu.
As Chiba was sparring with Koizumi, her eyes changed back to her brown color as her chakra ran out, signifying the end of the match just as Chibas wooden sword was inches from her neck.
"Thanks to the sharingan, you already know one of the most powerful sword techniques in the world, you just apply it too rigidly. When I'm gone your mission is to breakdown my sword techniques and add to it, making it your own. I'll leave a shadow clone behind to tutor you, you won't be able to spar with it but it will give you advice for about a month before disappearing" Chiba said as his clones disappeared and the experiences of writing entered his brain.
Raising his hands into a plus sign, two more shadow clones with the combined experience sat down and began practicing their Kanji more, wanting to better than just adequate enough.
Chiba watched Koizumi practicing by herself for a few seconds before nodding and going inside, he then took out a wooden box that he had received from Kushina.
Opening it up was a hundred paper talisman with a red boarder on the outside, these were papers used to make explosion tags! Next to the paper was a bottle of black ink that had somehow held onto chakra like a battery.
Chiba took these and left for the death forest training grounds. Jumping over the fence that kept the animals inside, Chiba went deep into the woods as he saw all manner of animals that radiated chakra.
Finding a large tree, Chiba sat down on the large branches as he took out the paper and ink, mentally going over the instructions he'd been given. Chiba didn't want to be anywhere near Koizumi or his house when practicing with explosions tags, so the death forest was his best choice.
Picking up his brush, Chiba started moulding the chakra inside of him into the formula provided to him, and poured that chakra into the brush. He wrote down what was taught to him by Kushina as he continued to pour his chakra into the brush and ink.
After a few 5 minutes of painstacking writing, Chiba had finished his first explosion tag and he immediately wanted to try it! Infusing his chakra into the tag, he threw it at a distant tree as he actives the snake seal.
*Poof*
Chiba was expecting a powerful explosion, only to see no damage was done to the tree with only dust and dirt kicked up from the "explosion".
'.....Well I never expected to be a once in a generation Fuinjutsu genius anyway.' Picking up another paper, Chiba got back to writing.
When Chiba agreed to become Kushina's disciple, he stayed up all night brainstorming ideas on how to become stronger through the use of Fuinjutsu, becoming a Jinchuriki was obviously first thought.
This was not possible as the tailed beasts were being heavily guarded by the villages, but it was his starting point for ideas.
The Tailed beasts are entities made entirely of chakra, making them have an overwhelming level of chakra compared to humans and constantly regenerate the chakra at a fast rate.
The reason Naruto was so overwhelming powerful, was because he had the equivalence of a nuclear reactor constantly pumping him full of chakra at all time.
With that idea in mind, Chiba's second thought was shadow clone! Shadow clones are just copies of the user made entirely of chakra, so in theory, they too can be sealed inside of a person!
The problem with this however, is that shadow clones dont regenerate chakra and are constantly leaking energy just existing, so they could probably last a month before losing all of their chakra, and if you used them a few days before they disappeared, you'd barely get any chakra from them.
As he thought of this, Chiba remembered a fact.
The ten tailed beast is made up of the god tree that was fused with Kaguya, both physical being. Hagaromo and Hamura then seperated the chakra and the body of the ten tailed beast, dividing its chakra and creating the nine tailed beasts while sending the empty husk of a body to the moon.
This meant that when Madara and Obito sealed the ten tails inside of them, they were sealing an actual physical creatures with a physical body inside of themselves and becoming its Jinchuriki!
The moment Chiba realized this, he thought of the frog, Gamabunta, who went toe to toe with the one tailed beast. Making the frog at the very least low kage level! If Chiba became the 'Jinchuriki' of a powerful animal like that, then his need for chakra would be satisfied!
This idea was reinforced when he thought of the Inuzuka clan, they did something similar to what Chiba was planning to do. They raised a dog from a puppy to become their partner and when they become familiar enough, they can fuse with one another and combine their power, becoming pseudo Jinchuriki of one another.
The more he thought about it Chiba was convinced that he could become the jinchuuriki of a physical animal, the only thing to decide is which animal.
He knew that even one of the strongest animals in the world like Gamabunta, could barely hold back the weakest tailed beast for a few seconds. Thankfully the animal that Chiba had set his eyes on was much better than Gamabunta, and for all he knew, better than even the tailed beast when it came to becoming its Jinchuriki!
Chiba's goal was to seal the largest creature in this world inside of himself, the animal he was thinking about was five times larger than even the ten tailed beast!
Chiba planned on sealing the turtle island, Genbu!
There exists a turtle so large, that an entire ecosystem had been formed on its back and is repeated mistakes as a land mass and not a creature.
This turtle was incredibly slow and had very little to absolutely no attack power to defend itself, which only attracted Chiba even more!
Unlike in the naruto anime, things had to make sense here as it was the real world. There is absolutely no way that any physical creature that large could aquire the calories necessary to survive. Whales were only 100 ft long and they needed 400,000 calories a day, meanwhile Genbu was over 16,000 ft long. This can only mean one thing!
This turtle must be able to absorb an insane amounts of chakra from the air and use it as fuel for it's large body!
While Chiba didn't know the conversion rate of chakra to calories, Chiba roughly estimated that a creature as large as Genbu needed 64,000,000 calories just to sustain itself each day. The amount of chakra necessary for the large creature just to survive was immense, and Chiba planned on making it his own, there was only one problem.
This giant turtle was in the land of lightning and was very special to them. They had been taking care of this turtle since the start of their village and even created building on its back, so Chiba knew he'd have a hard time sealing the creature inside of himself even though the creature was defenseless.
The only other thing stopping Chiba from becoming obtaining such power was his lack of skill in Fuinjutsu, which is why he'd put his sword training on the back burner as started focusing more on his Fuinjutsu.
Standing up, Chiba threw out his second explosion tag against a tree.
*Pang*
With slight noise, Chiba saw that there was now a tiny dent in the trees trunk from the explosion, causing a smile to appear on his face.
Chiba had spent most of his time training his explosion tags as he knew hed have a tough time doing so in the war.
Chiba will have to manage his chakra wisely as he always needed to have enough just in case a Jonin ninja appears and he has to use his observation Haki's future sight to defend.
With that though in mind, Chiba doubled down his efforts as he began creating more explosion tags, desperately wanting to become good enough to learn the eight trigram seal.