The Scroll of Seals is a forbidden scroll overseen by successive Hokage, containing numerous forbidden jutsu.
The reason these jutsu are sealed is either due to their extreme difficulty in mastering or because of their severe side effects one misstep can lead to dire consequences.
Despite the high difficulty and dangerous side effects, anyone who can master them gains immense power.
The Fourth Hokage, famed across the shinobi world as the Yellow Flash, earned this title thanks to his mastery of the space-time ninjutsu Flying Thunder God Technique—a jutsu recorded in the Scroll of Seals.
Similarly, Orochimaru was able to transfer his consciousness into other bodies and pursue eternal life because he successfully mastered the Living Corpse Reincarnation Technique, which also originates from the Scroll of Seals.
Once mastered, these techniques grant incredible power. So, despite their side effects, many covet the Scroll of Seals.
"Flying Thunder God Technique and Eight Gates Release Formation!"
Among the forbidden jutsu in the Scroll of Seals, Uchiha Fugaku was naturally intrigued—especially by the Flying Thunder God Technique and the Eight Gates Release Formation.
The Flying Thunder God Technique, a rare space-time ninjutsu, earned the Fourth Hokage the title of Yellow Flash—its power needs no further elaboration.
As for the Eight Gates Release Formation, its most prominent user, Might Guy, was able to injure Six Paths Madara after opening the Eighth Gate—undeniable proof of its devastating power.
"I wonder if I possess talent for space-time ninjutsu…"
Between the two, the more difficult one to master is undoubtedly the Flying Thunder God Technique.
It requires exceptional innate talent for space-time ninjutsu. Without such a gift, even a lifetime of training would yield little progress.
The best example is the trio of Tokubetsu Jōnin—Genma Shiranui, Raido Namiashi, and Iwashi Tatami.
As the Fourth Hokage's personal guards, they were directly taught the Flying Thunder God Technique.
However, due to their lack of natural affinity for space-time jutsu, all three could only perform the technique when activating it together—and even then, with far less flexibility and mobility compared to the Fourth Hokage. It became a transportation tool, not a viable combat technique.
Fugaku didn't know whether he had talent for space-time jutsu, but if he could get his hands on the Scroll of Seals, he definitely intended to try.
He wanted to see whether he had what it took to master the Flying Thunder God Technique.
"Compared to the Flying Thunder God, the Eight Gates demands far less innate talent."
While the Eight Gates technique is also difficult to master, it's more accessible.
In Konoha, only two people have ever trained to the point of opening all eight gates—Might Duy and his son, Might Guy.
Despite being talentless in ninjutsu, they were gifted in taijutsu—more so than most shinobi. That's how they were able to reach the final gate.
Furthermore, since several others have managed to learn the technique at lower levels, it proves that although challenging, the Eight Gates is far easier to master than the Flying Thunder God Technique.
Fugaku had confidence in his taijutsu abilities.
He did not believe his talent in taijutsu was inferior to Might Duy or Might Guy. If they could master the Eight Gates, he believed he could too.
"The troublesome part is the technique's side effects…"
The Eight Gates technique is immensely powerful—but at a great cost.
It forces the body to operate under extreme strain. Especially after opening the Eighth Gate, one gains strength many times that of a Kage, but at the price of death.
Might Duy died after opening the Eighth Gate. Might Guy would have died as well, if not for Naruto's Six Paths powers healing him.
"The side effects are indeed severe—but I have a way to bypass them."
Fugaku was particularly interested in this jutsu because he had a way to bypass the fatal drawback of the Eighth Gate.
That's right—he could avoid the certain death that comes with opening all eight gates.
The method was simple: he wouldn't use the technique in reality, but within his True Illusion.
Within a True Illusion, any damage inflicted on an enemy is reflected onto their real body, while any damage received by the user has no effect in reality.
So even if he "dies" after opening the Eighth Gate within the illusion, his real body remains unharmed.
This was Fugaku's unique solution to the Eight Gates' fatal cost—something only he, with the True Illusion dojutsu, could achieve.
"True Illusion combined with the Eight Gates…"
Fugaku's eyes lit up with anticipation.
This combination was undeniably powerful—certain to greatly enhance his strength.
"This is the perfect opportunity!"
Fugaku had long wanted to acquire the Eight Gates technique.
Now that the Third Hokage had ordered Uchiha Shisui to steal forbidden Sharingan techniques—leading to a theft incident—this was the perfect chance to steal the Scroll of Seals.
He stepped out of the secret chamber and called out:
"Someone come. Who was on guard duty today? Did anyone notice suspicious activity?"
Soon, word of the break-in at the Uchiha clan head's secret chamber spread throughout the clan.
Before long, the entire village of Konoha knew about it.
Many clans opposed to the Uchiha secretly mocked them.
A break-in at the heavily guarded estate of the clan head—during broad daylight—was an utter humiliation for the Uchiha.
At the Sarutobi estate, the retired Third Hokage had returned from the Hokage Tower.
Whoosh!
A young man with silver hair and an ANBU mask appeared in a blur, kneeling on one knee.
"Hokage-sama, we've just received word—Uchiha Fugaku's secret chamber has been infiltrated. The full extent of the losses is still unknown."
This was Kakashi Hatake, the genius who had made history by becoming a jōnin at the age of twelve.
"I already know," the Third Hokage replied calmly, unsurprised.
In fact, he had learned about it hours ago from Uchiha Shisui himself.
Not only that—he had ordered Shisui to transcribe the stolen forbidden Sharingan techniques and preserved a copy for himself.
While the Uchiha's eye techniques were useless to him, they were still worth collecting.
"Hokage-sama, I suspect an outsider may have infiltrated the village. Should we increase the security at the scroll vault?" Kakashi asked.
"There's no need," Hiruzen shook his head. "The vault's security is already sufficient. Besides, we're short on manpower due to the heavy mission load."
Kakashi didn't know the truth but Hiruzen did.
The infiltrator wasn't an outsider it was Shisui. So there was no need to increase security.