Naruto: Uchiha Survivor Forced to Save the Shinobi World

When Uchiha Shinji awakened his Mangekyō Sharingan, he realized the potential of Susanoo Tomoshibi.

After using it to channel Uchiha Fugaku's Mangekyō Sharingan, he experienced its power firsthand.

While channeling another pair of Mangekyō Sharingan didn't exactly double his own dojutsu power, it did enhance his ocular abilities and granted access to additional dojutsu, making subsequent battles much easier for him.

However, after evolving his eyes into the Eternal Mangekyō Sharingan, Shinji discovered that using Susanoo Tomoshibi to channel an additional pair of Mangekyō Sharingan brought only limited improvements to his dojutsu power.

And as his own Eternal Mangekyō Sharingan grew stronger, the power boost from channeling ordinary Mangekyō Sharingan through Susanoo Tomoshibi became negligible—though it still granted access to the unique dojutsu of those eyes.

At first, Shinji thought this was because of the significant disparity between the power levels of the two pairs of eyes. But when he was forced to channel a pair of high-purity Byakugan from the Ōtsutsuki branch family on the moon, he realized something unusual:

Using Susanoo Tomoshibi to channel the Byakugan granted a greater power boost than channeling another pair of Mangekyō Sharingan—and by a significant margin.

This was perplexing because, in terms of raw dojutsu power, the Byakugan couldn't compare to the Mangekyō Sharingan.

Yet, the Byakugan provided greater enhancements when channeled through Susanoo Tomoshibi.

After multiple experiments, Shinji began to uncover a secret about Susanoo Tomoshibi:

It provided significantly greater power boosts when channeling different types of dojutsu Bloodline Limit rather than the same type.

This revelation led Shinji to reassess the true potential of Susanoo Tomoshibi.

The mechanism seemed to complement missing elements by absorbing unique traits and advantages from various types of dojutsu Bloodline Limit, maximizing his overall dojutsu potential.

This explained why channeling a Byakugan offered a better power boost than another Mangekyō Sharingan.

Shinji's Eternal Mangekyō Sharingan already embodied the full traits and features of the Sharingan lineage, leaving little room for ordinary Mangekyō Sharingan to add anything meaningful.

Conversely, the Byakugan possessed unique abilities that the Sharingan did not, filling in gaps in his dojutsu arsenal.

Revisiting Susanoo Tomoshibi's Potential

Previously, Shinji had been preoccupied with his plans for the Rinnegan and Tenseigan projects, leaving him little time to delve into Susanoo Tomoshibi's capabilities. But now that those plans were temporarily halted, he could focus on exploring its untapped potential.

Rubbing his chin in thought, Shinji pondered:

"Beyond the Sharingan, Byakugan, Rinnegan, and Tenseigan, what other dojutsu Bloodline Limit exist in the ninja world?"

While all dojutsu originated from the Ōtsutsuki clan's Byakugan, centuries of genetic mutation and evolution had given rise to various other unique Bloodline Limit.

Apart from the more common dojutsu, Shinji soon recalled two obscure ones: Hogan (Red Eye) and Ketsuryūgan (Blood Dragon Eye).

Hogan, a dojutsu once belonging to a bloodline clan from Kirigakure, was a particularly intriguing Bloodline Limit.

The abilities of the Hogan were extraordinary. In addition to granting the Byakugan's vision-through-walls ability, it provided heightened sensory perception, allowing its users to predict danger and make small-scale anticipatory judgments.

Even more impressively, the Hogan could create illusions that disrupted the Byakugan's perception, earning it the nickname "Byakugan Slayer."

Despite its potential, the Hogan was tragically underestimated in the original timeline. The Kirigakure bloodline rebellion wiped out the Hogan clan, leaving only one known survivor: Ranmaru, a disabled boy.

Yet even Ranmaru, an untrained, non-shinobi child, demonstrated Hogan abilities rivaling that of the Byakugan or a three-tomoe Sharingan.

This left Shinji wondering: What was the Hogan's true potential? Could it rival the Sharingan's Mangekyō-level abilities?

Ketsuryūgan, the Blood Dragon Eye, was another rare dojutsu that Shinji recalled.

This Bloodline Limit was native to the Chinoike clan, who had encountered Sasuke during his travels in the original timeline.

One Chinoike clan member, Chino, had even faced off against Sasuke in a genjutsu battle, demonstrating the Ketsuryūgan's formidable illusionary capabilities. While Chino ultimately lost, it was important to note that her opponent was none other than Sasuke, the reincarnation of Ōtsutsuki Indra.

Beyond its genjutsu prowess, the Ketsuryūgan had another unique ability: the power to manipulate blood.

By using its distinct chakra, a Ketsuryūgan user could detonate an opponent's blood, creating devastating explosions known as "blood bombs."

Expanding the Arsenal

"Hogan… Ketsuryūgan…"

These two dojutsu were the most accessible options for Shinji to experiment with.

There were others he could think of, too.

For instance, Boruto's Jōgan (Pure Eye) and Ōtsutsuki Isshiki's cross-patterned dojutsu were clearly distinct from the Sharingan. If channeled through Susanoo Tomoshibi, these rare Bloodline Limit could provide tremendous enhancements to his dojutsu power.

"It looks like my next step is to gather more diverse dojutsu Bloodline Limit."

In that moment, Shinji made up his mind.

When it came to dojutsu power, there was no such thing as too much.

Uchiha Madara spent decades awakening the Rinnegan—whether due to using Izanagi or insufficient ocular strength.

If Shinji wanted to avoid enduring decades of effort like Madara, he needed to boost his dojutsu power as much as possible, as quickly as possible.

The more, the better.

Additionally, Shinji was deeply curious: Would channeling other unique dojutsu Bloodline Limit through Susanoo Tomoshibi unlock unexpected abilities?