After deactivating his Sharingan, Mo Yu's fatigue gradually faded away.
For him, activating the Sharingan was still quite taxing, both in terms of chakra and physical stamina, which were both consumed at an accelerated rate.
However, as a trump card, the Sharingan was undoubtedly the best.
Mo Yu noticed that after activating the Sharingan, his mental strength had slightly increased, and the area between his brows felt tight and slightly warm.
As expected, the improvement in the Sharingan was closely related to the mind.
The second stage of the Sharingan, the dual-tomoe Sharingan, was also known as the "Hypnosis Eye" or the "Genjutsu Eye." It allowed the user to both cast and resist genjutsu, and this was also connected to mental power.
As for the third stage, the "Mangekyō Sharingan," it was still far from Mo Yu's reach, so he didn't think about it for now.
With 50 gold coins and no deductions, Mo Yu felt quite confident.
He was determined to make the best use of this and enhance his strength, arming himself to the teeth.
Mo Yu immediately went for his first goal.
"System, exchange for the Water Thunder Body Refining Technique."
Mo Yu had wanted this technique since his first exchange, but due to a lack of funds at the time, he had to let it go.
Now, he finally had the chance to fulfill his wish.
Mo Yu firmly believed that no matter what level of strength one reached, the foundation was always the body, and it should never be underestimated.
With a flash before his eyes, the Water Thunder Body Refining Technique appeared.
"10 gold coins. Would you like to exchange it?"
"Yes!"
A surge of information flooded into Mo Yu's mind, all related to the Water Thunder Body Refining Technique.
"Balance: 40 gold coins."
Not yet checking the details of the technique, Mo Yu continued his exchange.
The ninjutsu he currently mastered, aside from the most basic Clone Technique, were three D-rank ninjutsu:
Fire Style: Fireball Jutsu
Genjutsu: Naraku Vision
Eight Gates: Opening the First Gate
These three techniques were sufficient for an average genin.
However, now that Mo Yu had offended the Uchiha, and knowing their proud nature, they would never just let him go.
Moreover, he hadn't forgotten that he had killed people like Arima Seiichi, and those behind them were small ninja clans.
While these smaller clans hadn't come after him yet, Mo Yu was certain it was only a matter of time before they suspected him.
Given the dual threats looming over him, Mo Yu needed to master more powerful ninjutsu for self-preservation.
"System, upgrade Fireball Jutsu to Great Fireball Jutsu, and also exchange for the second gate of the Eight Gates: The Rest Gate."
"Upgrade C-rank Fire Style: Great Fireball Jutsu. Consumes 5 gold coins."
"Exchange for Eight Gates: The Rest Gate. Consumes 5 gold coins."
"Exchange successful! Balance: 30 coins."
Another wave of information rushed into Mo Yu's mind, much more extensive than the previous one.
However, Mo Yu merely furrowed his brows slightly and began absorbing the information without any further reaction.
Great Fireball Jutsu was the signature technique of the Uchiha clan. Although it was only a C-rank technique, it was quite exquisite. If fully unleashed, it could rival a normal B-rank jutsu. This was why the Uchiha loved using it.
It consumed little chakra, had significant power, and looked impressive—perfect for showing off.
The founder of this technique seemed to have utilized the power of the Uchiha bloodline, and only those who had the Uchiha bloodline could bring out its full potential.
Fortunately, Mo Yu possessed the Uchiha bloodline.
Moreover, with the ninjutsu system imparted to him, he had mastered it with 100% proficiency.
In other words, Great Fireball Jutsu in Mo Yu's hands was already as powerful as a B-rank ninjutsu.
For him, it might be a better trump card than activating the Sharingan.
From the information about Great Fireball Jutsu, Mo Yu received an interesting tidbit:
"C-rank Great Fireball Jutsu can be upgraded to B-rank Great Dragon Fire Jutsu. Requires 50 gold coins."
Mo Yu had a bold idea.
Perhaps Great Fireball Jutsu was part of a series of techniques.
First, there was the basic Fireball Jutsu, then the Great Fireball Jutsu, followed by the Great Dragon Fire Jutsu. Could it be that it could continue upgrading to A-rank and even S-rank techniques?
Now, Mo Yu completely understood why members of the Uchiha clan, as long as they had fire-style chakra, would all learn Great Fireball Jutsu. This step-by-step upgrading system was truly a genius idea.
50 gold coins—Mo Yu no longer had enough.
But even if he did have enough, he wouldn't upgrade it.
B-rank ninjutsu was extremely powerful, but it would drain all his chakra if he used it, leaving him unable to execute it.
Only exceptionally gifted Chūnin and Jōnin could cultivate B-rank techniques.
Even the legendary Three Ninjas might not all have mastered B-rank ninjutsu at this time.
Once ninjutsu reached the B-rank, it began to possess large-scale destructive power, no longer the small-scale techniques of C- or D-rank.
A ninja who mastered B-rank ninjutsu could easily kill hundreds of elite soldiers.
Just as Mo Yu was preparing to continue his exchanges, his expression slightly changed.
"Who's there?"
Mo Yu leaped off his bed and dashed into the yard.
By now, the sky outside had darkened, and it was eerily quiet, with not a single sound.
It was this eerie silence that made it so strange—no birds were chirping, no insects buzzing, just an unsettling stillness.
"Come out, no need to hide."
Mo Yu's voice was low as his eyes subtly swept around the surroundings.
A figure stepped out from behind a tree in the yard, the sound of footsteps crunching on fallen leaves.
Mo Yu breathed a sigh of relief in his mind.
He wasn't sure if someone was hiding nearby, but after activating his Sharingan, his mental power had greatly increased.
Earlier, he had only faintly sensed the presence of a living being, so he came outside to investigate. He hadn't expected to find someone.
"Who are you?" Mo Yu demanded.
"Arima Seiichi."
The person who stepped out from behind the tree said coldly.
He was a young man, probably in his twenties, with a rugged face like a block of stone. The killing intent emanating from him was palpable, heading straight for Mo Yu.
If it had been any other freshly graduated ninja, they probably would have been scared stiff by this murderous aura.
But Mo Yu, with his strong will and the experience imparted by the system, had ways to handle killing intent, so he remained unfazed.
"Arima?" Mo Yu pretended not to know.
Arima Seiichi, surprised that Mo Yu wasn't intimidated by his killing intent, continued: "Yes. My brother, Arima Seiichi, was the unworthy one."
Mo Yu immediately understood in his heart, but kept up the act of not knowing. "Then what are you here for?"
"To kill you!"
For the first time, a change in emotion appeared on Arima Seiichi's stiff face as he spoke, "The Uchiha clan said that my brother and his two friends came to find you before they went missing. Their disappearance has something to do with you."