Obito had only just become the Ten-Tails Jinchūriki and had yet to fully adapt to his new power.
Facing Isshiki's sudden attack, his reaction was a fraction too slow.
He instinctively condensed a Truth-Seeking Ball and transformed it into a shield in front of himself.
However.
Truth-Seeking Balls were of little use against someone at the Kekkei Mōra level.
'Crack!'
Isshiki simply swept his black rod forward and shattered the Truth-Seeking Ball.
At the same time, his right hand reached toward Obito.
His objective was to devour the Ten-Tails' Chakra within his body!
"Hmm?"
Obito's pupils contracted.
Although this was his first time using Truth-Seeking Balls, he already understood their basic properties.
They could nullify ordinary Ninjutsu.
Yet Isshiki had shattered one so easily?
"Are you pretending I'm not here?"
Seiryū's perception had covered the entire area from the beginning, so he had naturally tracked Isshiki's movements.
He threw a punch from a distance.
Terrifying dragon-shaped fist force tore through the air!
"Damn it."
Isshiki did not dare underestimate Seiryū's attack.
His scarlet Rinnegan flashed, and an immense repulsive force surged outward.
'Boom!'
The two attacks collided.
A deafening explosion erupted as the shockwave swept across the battlefield.
Obito, who was closest to the clash, was forced backward by the aftermath alone.
His feet carved two long trails through the ground before he finally stabilized himself.
His expression immediately became grave.
"Who are you?"
"This kind of power."
Madara could no longer remain seated.
He rose to his feet and stared toward the two newcomers with his Rinnegan, his expression unusually solemn.
"The level of the Sage of Six Paths?"
Madara had already begun approaching that realm himself.
Yet the mere aftermath of these two people's attacks had been enough to force back Obito after he became the Ten-Tails Jinchūriki.
That alone proved one thing.
Those two possessed power on the level of the Sage of Six Paths!
How could people like this exist in the shinobi world?
Seiryū casually swept aside the dust filling the air and looked toward Obito.
"Yo, Obito."
He greeted him with complete familiarity.
"Why are you still so useless? You can't even suppress the Ten-Tails' will?"
"It's me. Seiryū."
"Seiryū?"
Obito frowned.
He had never heard that name before.
"That's right. I'm one of your best friends."
Seiryū immediately began talking nonsense again.
"Although you were always incredibly jealous of me."
A grin spread across his face.
"What? You want to know why?"
"Obviously because Rin is my girlfriend."
The Obito from Seiryū's own space-time really had been extremely jealous of him.
All because of Rin.
"Rin."
Hearing that name, Obito's eyes wavered.
For a brief instant, his concentration slipped.
The Ten-Tails' will immediately surged against his consciousness.
"Argh!"
Obito felt as though his mind were being torn apart.
His body began swelling grotesquely, almost like an inflated balloon.
It was a sign that he had yet to completely control the Ten-Tails.
However, Obito's willpower was extraordinarily strong.
He endured the Ten-Tails' mental assault by force.
And then.
He seized complete control of its power!
'Hum!'
Six Paths-level Chakra erupted violently, sending dust surging across the battlefield.
When the dust dispersed, Obito's appearance had changed.
A Six Paths cloak seemed to grow directly from his body.
A black staff rested in his hand.
Nine Truth-Seeking Balls floated behind him.
He had finally brought the Ten-Tails completely under control.
A true Ten-Tails Jinchūriki!
Seiryū raised an eyebrow.
"Oh?"
"So the strong-willed Obito finally showed up."
"Not bad. Pretty impressive."
"Who exactly are you?"
Now that he had completely mastered the Ten-Tails' power, Obito's confusion disappeared.
His Mangekyō Sharingan and Rinnegan stared coldly at Seiryū.
"A friend of yours from another space-time."
Seiryū smiled even more brightly.
"And, well, Rin's boyfriend."
"But I didn't expect you to be the villain in this world."
"That's actually pretty interesting."
"Another space-time?"
Obito narrowed his eyes.
"Rin's... boyfriend?"
He did not believe a word of it.
But hearing this stranger repeatedly call himself Rin's boyfriend still made him inexplicably furious.
"I don't know who you are."
Obito's voice turned cold.
"But you can die."
With a thought, one of the Truth-Seeking Balls behind him transformed into a projectile and shot toward Seiryū.
He intended to kill the bastard who dared insult the dead Rin!
"Looks like you don't believe me."
Seiryū shook his head.
"Just like the Obito from my world."
"You refused to believe it back then too. The emotional shock was so bad that you even awakened the Mangekyō Sharingan."
Facing the incoming Truth-Seeking Ball, Seiryū merely raised his right hand.
He caught it directly.
At his current level, a Truth-Seeking Ball was no longer much of a threat.
"I don't particularly want to fight you, considering we're friends."
Seiryū grinned.
"But since you're apparently the villain in this space-time, I suppose I have no choice."
"As a shinobi of Konoha, I'll reluctantly deal with you."
Seiryū took a single step.
The distance between them vanished instantly.
'Boom!'
Before Obito could react, Seiryū pressed a Rasengan with Chakra compressed to an extreme degree against his chest.
The Compressed Rasengan erupted.
Obito was blasted away in an instant!
"Rasengan?!"
Naruto stared in shock.
This mysterious young man who had appeared out of nowhere and possessed terrifying strength could use the Rasengan too?
Who exactly was he?
"Rasengan."
Minato frowned slightly.
Then he looked more closely at Seiryū's face.
As though suddenly remembering something, disbelief appeared in his eyes.
"Could it be."
"You seem to remember something."
At some point, Seiryū had already appeared beside Naruto and Minato.
He smiled toward the Fourth Hokage.
"As expected of you."
Then Seiryū turned toward Naruto.
His perception swept over the young shinobi, and an expression of realization appeared on his face.
Just as expected.
Seiryū greeted Naruto familiarly, deliberately adopting the tone of an old man.
"Yo, kid."
"Long time no see."
"Do you still remember me?"
"I am Sage Seiryū, practitioner of the Technique of Eternal Youth!"
There was a seal placed on Naruto's memories.
In other words.
This really was the same Naruto who had once traveled to Seiryū's space-time with Yamato through the power of the Dragon Vein.
What a coincidence!
No.
Perhaps it was not entirely a coincidence.
Seiryū and Isshiki arriving in this particular space-time might have been related to Naruto.
Naruto had once crossed into another space-time, creating a subtle connection between the two timelines.
It might have been precisely because of that connection that Seiryū and Isshiki had been drawn here.
As for arriving specifically during the Fourth Shinobi World War.
That was probably coincidence.
This space-time's history had simply progressed to this point.
Hearing the title "Sage Seiryū," Minato took a deep breath.
His expression remained filled with shock.
"So it really is you."
"A shinobi from another space-time actually came here."
As for how Minato knew anything about another space-time.
During the Nine-Tails' attack years ago, Minato had left a portion of his Chakra inside Naruto.
Because of that, he had indirectly become aware that Naruto had once traveled into another space-time.
Unlike Naruto, that fragment of Minato's Chakra had not had its memories sealed by his alternate self.
That Chakra had later appeared when the Nine-Tails nearly broke free inside Naruto.
After reinforcing the seal, the Chakra was exhausted.
However, it had not simply disappeared.
Like the memories of a Shadow Clone returning to its original body, those experiences eventually returned to Minato's soul.
Because of that, he retained a vague impression of what had happened.
And now, he finally remembered Seiryū's identity.
A shinobi from another space-time.
Someone who called himself Sage Seiryū.
And claimed to have mastered the Technique of Eternal Youth!
(To be continued.)