Only One Path Left

Shirou Emiya...

Would you regret your naïveté and foolishness?

In this world, Black Zetsu rarely communicated with anyone. The person it had spoken with the most was Shirou Emiya.

It wanted to mock Shirou Emiya.

That thought had always lingered in Black Zetsu's mind.

Black Zetsu had always regarded Shirou Emiya as one of its pawns, only to be betrayed and discarded by Shirou Emiya on the eve of its plan's great progress. The feeling was rather unpleasant.

Black Zetsu had seen the Crystal Coffin stored by the Senju Clan more than once.

The last time had been two years ago, when Black Zetsu had secretly infiltrated Tobirama Senju's Secret Chamber and arrogantly mocked Shirou Emiya's naïveté and foolishness before the Crystal Coffin kept by the Senju Clan.

Now...

Shirou Emiya had truly been resurrected.

It truly had the chance to mock him in person.

It even had the chance to reactivate this pawn, the only pawn capable of leading its plan to success!

Yet Black Zetsu did not dare indulge in a momentary pleasure at this time. It needed to carefully consider its choice.

Because it had a new pawn.

Madara Uchiha.

This was an entirely new pawn.

This pawn was following its plan step by step.

Although Madara Uchiha had only taken the first step and the future was still unclear, it already had a mature plan for how to make use of Madara Uchiha.

As for Shirou Emiya...

Shirou Emiya was a proven example.

Back then, it had not needed to do anything. It had not even guided him properly, yet Shirou Emiya had handled everything himself in order to destroy the Ninja Sect.

Of course...

The possibility that this era was an exception could not be ruled out.

It did not know what state the resurrected Shirou Emiya was in.

This era no longer had the Sage of Six Paths' corpse for him to study. There were only Ashura's Chakra Reincarnation and Indra's Chakra Reincarnation...

It seemed...

That was not much of a problem either.

Shirou Emiya's true strength had never been his power.

Shirou Emiya's true strength lay in his genius-like mind, in the human experimentation techniques that had stemmed from his pursuit of advances in human medicine.

Having personally witnessed the miracles Shirou Emiya had created using the Sage of Six Paths' corpse, Black Zetsu truly could not imagine that a genius like Shirou Emiya, armed with the theories it provided, would be unable to solve the experimental problem of creating the Rinnegan.

The only trouble was...

It had lived for over a thousand years. Would Shirou Emiya still believe it? A monster that had lived for over a thousand years surely could not have an ordinary identity.

Uh...

He probably would.

It only needed to make up a convincing reason.

For example, it could claim to be the will of the God Tree. That seemed little different from claiming to be Kaguya's will...

To be honest?

It seemed not to matter anyway.

Because Shirou Emiya knew of Kaguya's existence.

Most people of that era knew of Kaguya's existence. They revered Kaguya as Goddess Kaguya of the Rabbit, who served the God Tree.

When it had deceived Shirou Emiya, it had told him that Chakra was not a power ordinary people could wield, and that only by falling into the right hands could it avoid bringing disaster upon the world.

Who were the right people?

Naturally, it was Kaguya Otsutsuki, the Goddess Kaguya of the Rabbit worshipped by humanity. Only the Goddess Kaguya of the Rabbit could decide who Chakra belonged to.

Wait...

Had it said all that?

Black Zetsu tried hard to recall every detail of its conversations with Shirou Emiya. It seemed that it really had mentioned its desire to resurrect Goddess Kaguya of the Rabbit to Shirou Emiya. Since Shirou Emiya had gained power from the God Tree Remnants, he too believed in the God Tree and Goddess Kaguya of the Rabbit, who served it...

It...

It seemed to have said far too much back then!

Black Zetsu could only anxiously recall the secrets it had not revealed to Shirou Emiya. It seemed that only its true identity and the method of resurrecting Kaguya remained...

Because truly resurrecting Kaguya would definitely require someone to sacrifice themselves as the vessel for her revival. That secret could not be leaked under any circumstances.

Fortunately...

It had kept that secret.

Yet it was also because it had kept that secret, even withholding every step from Shirou Emiya, that the plan which had nearly succeeded went astray and failed...

But...

It had already revealed its intention to resurrect Kaguya.

"..."

Black Zetsu almost wanted to sweat.

That was not a reaction a creature like it should have.

A thousand years ago, it had been far too young and naïve. It had actually exposed so many of its thoughts before Shirou Emiya. Fortunately, Shirou Emiya had also believed in the God Tree and innocently trusted it...

Really...

It had been so ignorant and reckless in its youth...

How had it been so naïve back then?

It had actually laid bare so much before one of its pawns!

After enduring the long passage of time, Black Zetsu was beginning to understand the awkwardness humans felt after growing up: embarrassment and regret over the things they had done when they were young.

At this moment...

Did it still have any choice?

No matter what Shirou Emiya was thinking...

No matter how many doubts Shirou Emiya had about its identity...

It...

It seemed it had no choice but to choose him.

Black Zetsu suddenly realized the predicament it faced. Because Shirou Emiya knew too many secrets, it could only choose Shirou Emiya as its pawn!

If the resurrected Shirou Emiya revealed the secrets of the Ancient Era, or even disclosed its existence, then Madara Uchiha, that pawn, would likely become unusable as well...

Unless...

It hid forever!

But Shirou Emiya would certainly reveal the secrets of the Ancient Era to this era. It did not know how long it would have to hide before it could ever stop.

Actually, Shirou Emiya would do...

After all, Shirou Emiya was quite an impressive pawn.

Back when it had been despondent, believing that its plan to resurrect Mom would never see the light of day, Shirou Emiya had appeared out of nowhere and illuminated the life Black Zetsu had thought would remain dark forever.

"Wait..."

"Could it just be my imagination?"

"I should first go check Shirou Emiya's Crystal Coffin..."

Black Zetsu's figure quietly slipped underground and noiselessly made its way toward Tobirama Senju's storage chamber, because it happened to know the location.

Very soon.

Black Zetsu arrived at the chamber.

When Black Zetsu saw the shattered crystals scattered all over the chamber, it could tell they had only been broken recently and had not yet been cleaned up. The fractured edges were fresh, still free of dust.

The half-corpse inside the Crystal Coffin...

Had naturally vanished without a trace.

Black Zetsu immediately concluded that the Shirou Emiya it had seen had truly been resurrected. It even knew that his resurrection was certainly related to Tobirama Senju.

That Tobirama Senju...

Had truly used half a corpse to resurrect Shirou Emiya...

That man wanted to use Shirou Emiya to treat the gravely injured Hashirama Senju!

Black Zetsu thought of the battle between Madara Uchiha and Hashirama Senju, thought of Hashirama Senju's severe injuries and coma, and immediately guessed Tobirama Senju's purpose!

That man...

Had really found the right person!

Hashirama Senju had suffered such severe injuries in that battle. In the entire thousand-year history of the Shinobi World, if anyone could save Hashirama Senju...

Other than the Sage of Six Paths...

It was probably only Shirou Emiya.

"No..."

"Something seems a little off..."

"After being resurrected, Shirou Emiya is helping save Hashirama Senju?"

Black Zetsu instinctively began paying attention to Shirou Emiya's situation. It recalled the conversation between Shirou Emiya and Tobirama Senju that it had overheard.

A thought suddenly surfaced in Black Zetsu's mind, one so terrifying that it continued to spread through its thoughts.

"Hashirama Senju is Ashura's Chakra Reincarnation..."

"Hashirama Senju ended the war and put an end to the Warring States Period that had lasted for a thousand years. At the very least, he recreated a Shinobi World that appeared peaceful on the surface..."

"That Shirou Emiya..."

"He must be able to sense that Hashirama Senju is the reincarnation carrying Ashura's Chakra. He is willing to help treat Hashirama Senju..."

"No..."

"That idiot Shirou Emiya..."

"Could he still believe Ashura's nonsense even now?"

This terrifying thought surfaced in Black Zetsu's mind, and it could not remain still for another moment. Its figure rapidly tunneled beneath the ground.

At this moment...

Black Zetsu was incomparably anxious!

If Shirou Emiya still believed that idiot Ashura, how many secrets would he reveal to the ninjas of this era!

It had to find him as soon as possible...

It had to learn what he was thinking as soon as possible!

If Shirou Emiya had not yet had the chance to reveal the secrets, it had to find a way to convince him to return to their original plan!

As for killing Shirou Emiya to keep the secrets...

That thought flashed through Black Zetsu's mind and disappeared.

Black Zetsu doubted that even if it had the chance to secretly frame Shirou Emiya and incite a conflict between Shirou Emiya and the ninjas of this era...

Come to think of it...

How much power did the resurrected Shirou Emiya still possess?

Although Shirou Emiya appeared to no longer have the Rinnegan, his own strength was still formidable. And what if, while it was plotting against him, he revealed its secrets without restraint because he knew nothing of the scheme?

Besides...

Black Zetsu truly did not want to.

Compared to Madara Uchiha, a troublesome new pawn that would cause problems in the future, Shirou Emiya, a pawn that had once nearly succeeded, was far easier to use.

This was the easiest path.

After truly seeing Shirou Emiya resurrected, no matter how many thoughts arose in Black Zetsu's heart, in the end, its thoughts would passively or actively narrow down to a single idea.

Convince Shirou Emiya... to stand on its side.