Anbu Assault

For an ordinary person, the idea of transforming oneself in just two months of intensive training would be nothing short of a dream. 

But let's not forget that Koshino had the app at his disposal and the advantage of the Multi-Shadow Clone Jutsu. With Guy's companionship, Koshino made comprehensive improvements in his abilities over two months, especially in overcoming his weakness in taijutsu, taking a solid step toward becoming an all-rounder ninja.

First, in terms of chakra:

While training in taijutsu, Koshino's physical fitness significantly improved. With the support of the Nara clan and the consumption of their secret medicines like they were free, Koshino broke through the limits of a Genin and moved toward the level of a Chunin in chakra capacity.

Just a step, or perhaps half a step more, and Koshino's chakra reserves would rival those of an average Chunin.

Such progress was nothing short of terrifying, and even Shikaku would likely be astounded by Koshino's rapid advancement!

Moreover, chakra progression was the slowest aspect of Koshino's training.

Regarding throwing weapon training:

By creating Shadow Clones daily for training, Koshino made remarkable progress in this area, completing the third stage of the Uchiha clan's training. Though Koshino couldn't yet match Itachi from the original story by throwing eight shurikens and hitting all targets simultaneously, he could easily throw six shurikens and hit his mark every time.

Thus, besides excelling in taijutsu, throwing weapons became another major area where Koshino showed significant improvement.

As for taijutsu training:

With the 10 kg weights providing a 10% acceleration in taijutsu training, Koshino's progress over two months was so significant that even Guy constantly praised his taijutsu skills, showing just how much Koshino had improved in this field.

It's no exaggeration to say that Koshino, even without using the Nara clan's secret techniques, could defeat an average Genin with just his throwing weapons or taijutsu.

In terms of overall strength, Koshino felt he was at the level of an elite Genin, unmatched among Genin, and could even defeat some average Chunin in an explosive encounter.

This fueled Koshino's desire to challenge Kakashi.

Given his confidence in defeating ordinary Chunin, Koshino wanted to test himself against a Jonin to see the gap between their abilities.

Of course, with progress in training came some regrets.

Koshino felt disheartened that the new secret technique in his app's development function remained at 99%, just shy of completion. This left Koshino somewhat anxious as he waited for the final breakthrough.

But there was nothing he could do!

With the new secret technique unfinished, Koshino made no significant progress in "jutsu," aside from perfecting the Nara clan's secret techniques he already mastered.

Able to deploy more Shadow Clones for auxiliary training, Koshino was already considering other areas to focus on while conversing with Guy.

"Throwing weapon training is complete, and taijutsu must be trained personally. Now, my Shadow Clones are free."

"After two months of rigorous training, it's time to return home and start on the Fourth Hokage's scroll, training in his secret techniques while improving chakra control."

"I'll train taijutsu with my main body and use Shadow Clones to practice the Fourth Hokage's techniques and chakra control."

"Speaking of chakra control, training with the Rasengan should improve my control, right?"

Suddenly recalling the Rasengan, Koshino's eyes lit up, knowing it was a must-learn jutsu for any transmigrator.

Unlike Kakashi's Chidori, the original story clearly detailed Rasengan's training method.

So, regardless of being the Fourth Hokage's disciple, the Rasengan was destined to be Koshino's.

Excited by the prospect of training in the Fourth Hokage's secret techniques and the Rasengan, Koshino set his next goal alongside challenging Kakashi.

Then, turning to Guy, Koshino prepared to ask for a leave to return home and review the Fourth Hokage's scroll.

But just as Koshino was about to speak, he noticed someone approaching rapidly. He and Guy exchanged a glance, both exclaiming simultaneously:

"Koshino, be careful!"

"Guy, be careful!"

"Boom!"

"Boom!"

Both Koshino and Guy cried out as the attackers suddenly appeared before them!

Among them, one attacker directly engaged Guy. Under Koshino's watchful eye, Guy fought the attacker to a standstill.

As for the other three attackers, Koshino noticed in his panic that they were targeting him!

"Are they from the Uchiha clan?"

"No, they're not!"

"The Uchiha clan wouldn't have the guts, and no one in Konoha would dare to attack a genius from another clan within the village."

"It couldn't be other ninja villages either; they wouldn't infiltrate Konoha under the Uchiha Police Force's watch."

"With all other possibilities ruled out, there's only one answer left!"

"Someone in the village wants to test my abilities, so they've sent these attackers!"

Quickly deducing the situation, Koshino, inheriting the Nara clan's excellent genes, instantly guessed the hidden motive behind the attackers, a smile forming on his lips.

Particularly when Koshino noticed the attackers wearing Anbu uniforms, he speculated on who might have sent them.

However, regardless of who sent these Anbu, Koshino, having made significant progress, didn't want to fail this test. So, as the three Anbu approached, kunai in hand and chakra flaring, Koshino didn't hesitate. He threw off the weights from his legs, forcing two Anbu back.

Facing the last Anbu, who wore a rabbit mask, Koshino drew six shurikens from his ninja tool pouch and threw them swiftly!

"Shadow Shuriken Technique!"

"Whoosh!"

"Whoosh!"

In the air, the six shuriken flew in elegant arcs, sealing off all of the rabbit-masked Anbu's escape routes, leaving the Anbu visibly shaken.

However, the rabbit-masked Anbu didn't consider a few shurikens a real threat.

Reversing his grip on his kunai, the Anbu swiftly deflected Koshino's shuriken.

But as the rabbit-masked Anbu prepared to unleash his chakra for a decisive strike, he noticed the confident smile on Koshino's face, which appeared just before his chakra flared.

"Is this the best the Anbu can do?"

"Haven't you realized you're already dead?"