'Boom!'
Gran Rey Cero collided with Shinra Tensei.
One was currently Seiryū's strongest technique, while the other was a Rinnegan Dōjutsu unleashed by Madara after absorbing the Chakra of seven Tailed Beasts.
Their collision was more powerful than anything that had come before it.
A world-shaking roar erupted. Even the distant Kumo, which had sealed its borders, could clearly hear the rumbling.
Once sound surpassed a certain threshold, it became a shockwave that spread outward from the point of impact.
'Boom, boom, boom!'
The shockwave swept across everything in its path and destroyed it.
The enormous lake nearby was blasted apart, exposing the muddy lakebed beneath it.
Layer after layer of earth was stripped away, while the surrounding mountain peaks collapsed beneath the force of the shockwave.
The seven Tailed Beasts summoned by Madara were sent tumbling across the battlefield and landed in disarray.
However, because they remained connected to the Rinnegan, the Summoning Jutsu was not dispelled.
An enormous crater, resembling the impact site of a meteorite, stretched across the battlefield. Even after countless years, it would likely remain.
The landscape had been permanently altered by human power, reshaped by the attacks of two shinobi.
The collision between their techniques had produced power comparable to a natural disaster.
The others, who had already retreated far from the battlefield and had been engaged in fierce battles of their own, were forced to withdraw even farther.
They could only use Ninjutsu to defend themselves.
Looking at the destruction in the distance, shock and unease filled their hearts.
The battle between Madara and Seiryū had become increasingly intense, and every collision between their Ninjutsu was more powerful than the last.
It even gave them the impression that this had already become a battle between gods.
According to myth, the battle between the Rabbit Goddess and the Sage of Six Paths had nearly shattered the entire shinobi world.
It must have possessed similarly incomprehensible destructive power.
If every attack from Madara and Seiryū caused this level of devastation, it might not take long for them to destroy the shinobi world.
Their attacks might already have approached the level of the Sage of Six Paths.
'Boom, boom, boom!'
At the centre of the battlefield, the thunderous echoes continued, and terrifying shockwaves swept across the surroundings.
Even the two people who had unleashed the attacks could not remain unaffected.
Both were forced to defend themselves with Ninjutsu, yet they were still pushed back and injured by the force of the collision.
"Cough, cough."
Madara coughed up blood while standing inside a half-body Susanoo.
Amenotejikara distorted the surrounding space, causing the shockwave to slide past him.
The full-power Shinra Tensei had nearly exhausted all the Chakra he had absorbed.
Even then, he had only barely managed to block Seiryū's attack.
"You actually blocked it. That is somewhat beyond my expectations."
Blood also trickled from the corner of Seiryū's mouth.
Although he had used Bakudō to defend himself against the instantaneous shockwave, the impact had still sent him flying backward.
He had been unable to avoid injury.
What surprised him even more was that Madara had actually endured his Gran Rey Cero.
Madara had truly risked his life.
Sensing the reduced amount of Chakra remaining in his body, Seiryū thought, 'This technique consumes an enormous amount of Chakra. Even with the Dragon Vein, I cannot use it a second time right now.'
With his current Chakra reserves, Seiryū could not unleash another Gran Rey Cero.
Its Chakra consumption was simply too great.
Before reaching the Six Paths level or the Kekkei Mōra level, Seiryū believed his Chakra reserves would not support a second use.
Watching the enormous mushroom cloud rising in the distance and the devastated landscape that resembled the aftermath of a natural disaster, Seiryū muttered, "Its power should be comparable to Naruto and Sasuke's final attacks at the Valley of the End."
"In this state, I should be comparable to Naruto and Sasuke at their peaks, when they possessed a portion of the Sage of Six Paths' power."
Naruto and Sasuke during their final battle at the Valley of the End had represented the peak of the shinobi world.
They had already surpassed Madara and the God of Shinobi, Senju Hashirama, from the Warring States Period.
Simply put, they had been the two strongest shinobi beneath the Six Paths level.
Seiryū believed that by combining Dragon Vein Chakra Mode with the Eight Inner Gates Formation, he had also reached that stage.
He was only one step away from the Six Paths level.
Seiryū's eyes flashed.
'And I still have one final trump card. I should be capable of fighting someone at the Six Paths level head-on.'
His final trump card was naturally Dragon-Human Hollowification combined with the Eight Inner Gates Formation.
At full power, Seiryū believed he could fight a Six Paths-level opponent directly.
Dragon-Human Hollowification would greatly strengthen his physique, compensating for the weakness caused by his body not yet being fully developed.
He estimated that he would become even stronger than Might Guy had been after opening the Eight Inner Gates Formation in the original story.
He would possess enough power to fight someone at the Six Paths level.
Of course, that state would place a tremendous burden on his body.
Power beyond his control would inevitably strain his body.
Seiryū estimated that even with High-Speed Regeneration, he would not be able to maintain it for very long.
However, that was enough for now.
Even if Madara became the Ten-Tails' jinchūriki and gained Six Paths-level power, Seiryū was confident that he could fight him.
Besides, it remained uncertain whether Madara could escape safely and successfully become the Ten-Tails' jinchūriki.
Given the opportunity, Seiryū would definitely eliminate Madara.
'Boom!'
Seiryū used Vollständig: Heavenly Eye to lock onto Madara's position.
He stomped against the ground and transformed into a streak of light as he rushed forward.
Seiryū threw a punch, forcing Madara, who had been preparing to leave, to defend himself.
'Boom!'
The half-body Susanoo swung its fist and shattered the force of Seiryū's punch.
However, Madara's movements were still interrupted.
Seiryū walked toward him step by step, revealing a cold and dangerous smile.
"Where do you think you are going? The battle is not over yet."
Madara gritted his teeth.
Intense killing intent flashed through his eyes, but beneath it lay a trace of shock and fear.
"What kind of secret are you hiding?"
Previously, Madara had simply believed that Seiryū's talent was extraordinary enough to grant him such power at his age.
Now, however, he began to doubt whether talent alone could truly explain it.
Perhaps Seiryū possessed some unknown secret.
"What do you think?"
Seiryū smiled noncommittally.
"Perhaps I am the reincarnation of an ancient Sage, just like you, and I am merely reclaiming my original power step by step."
Madara narrowed his eyes.
An ancient Sage reincarnated?
If that were true, it could explain how Seiryū possessed such power at his age.
Talent alone should never have been enough to reach this level.
"Heh. You do not actually believe that, do you?"
Seiryū sneered before continuing indifferently, "It does not matter. Do you have any more trump cards? If not..."
"Hmm?"
Before he could finish speaking, Seiryū sensed something.
He looked toward the sky and frowned slightly.
'Buzz, buzz.'
A strange sound suddenly came from high above.
Space-time seemed to twist at a single point, creating a bizarre scene.
It resembled what had happened when Seiryū had once invoked the power of the natural ley lines to gain complete control over the Dragon Vein.
'Crack!'
A sound resembling shattering glass rang out.
Space split open in the sky, revealing a pitch-black rift stretching across it.
The rift seemed to possess a powerful gravitational force, drawing in even the enormous mushroom cloud created by the earlier clash of Ninjutsu.
'Hum!'
Another humming sound erupted, and the spatial rift began to close.
However, just before it sealed completely, three dark figures shot out from the opening.
'Boom! Boom!'
They crashed down like small meteorites, producing two thunderous impacts.
Two more craters appeared across the already devastated ground.
Why were there only two impact sites?
Because two of the three figures had fallen together.
Vollständig: Heavenly Eye naturally captured the appearances of all three figures.
Seiryū stared at them, question marks practically appearing above his head.
'Why did these people appear now? Could the Dragon Vein Chakra have caused this?'
Seiryū complained inwardly.
There was no other reason for his reaction.
Through Vollständig: Heavenly Eye, he had seen three familiar faces.
"Three people fell out of the sky?"
Madara's Rinnegan also possessed extraordinary kinetic vision.
He clearly saw that the three dark figures emerging from the strange rift were three people.
Two adults and one child.
More importantly, Madara looked toward one of the landing sites, where a purple half-body Susanoo stood.
His expression became puzzled.
"Susanoo? Another member of the Uchiha Clan?"
Susanoo was a Dōjutsu belonging to those of the Uchiha Clan who had awakened the Mangekyō Sharingan.
'Boom!'
Powerful Chakra erupted from one of the craters.
A somewhat irritated voice sounded.
"Damn it. Why was there such a violent disturbance inside the space-time passage?"
A young man in his twenties climbed out of the crater.
He wore white clothing, possessed a pair of clear Byakugan, and held a red fishing rod in one hand. A red fishing basket hung from his waist.
His appearance was somewhat dishevelled.
He looked around in confusion.
"What period is this?"
Then his sharp senses detected something.
His gaze shifted toward the seven Tailed Beasts lying across the ground, none of which had yet risen.
He exclaimed in surprise, "Seven Tailed Beasts? What exactly is happening here?"
"Where is this?"
A man wearing a black cloak was equally surprised.
Long bangs covered one side of his face, while his visible right eye contained a complex Eternal Mangekyō Sharingan.
He scanned the surroundings, and his expression became grave.
"Seven Tailed Beasts? And Madara?"
"The First Hokage, the Second Hokage, Tsunade, Jiraiya, Orochimaru. Even my father is here?"
After sensing several familiar Chakra signatures, he became even more shocked.
What was going on?
Why were there so many familiar yet strangely different Chakra signatures in one place?
Some of these people should already have been dead.
How could their Chakra still exist?
"Phew. That was close. I really thought I was going to die."
Beside the Uchiha, a blond boy protected by the purple Susanoo had no idea what had happened.
He was simply relieved to have survived.
Moments earlier, they had been fiercely battling Urashiki Ōtsutsuki inside the passage.
Then, for some unknown reason, the entire space-time passage had begun shaking as though it were about to collapse.
They had seen only a flash of white light before suddenly falling from the sky.
Without Sasuke, the boy probably would have died upon impact.
"But where are we?"
The blond boy scratched his head and looked around.
The devastated landscape before him startled him.
"What happened here? Everything looks like it was torn apart by something terrible."
He had never seen destruction on this scale.
The entire area was barren and devastated.
This was clearly not natural.
It had been caused by a battle.
What kind of people could have caused such destruction?
"Warning! Warning! Space-time disruption detected! Space-time disruption detected! An unknown space-time force has interfered with the space-time transport. Current space-time unknown. Current space-time unknown."
At that moment, the pink turtle in the blond boy's hand suddenly opened its eyes and began issuing warnings.
Karasuki's voice carried an unusual trace of anxiety.
"This unknown space-time contains too many uncertainties. Please leave immediately to prevent unforeseen consequences."
As an artefact of the Ōtsutsuki Clan capable of travelling through space and time, Karasuki was extremely sensitive to space-time energy.
Just before they reached the coordinates selected by Urashiki Ōtsutsuki, another space-time force had suddenly interfered with their journey.
The two forces had collided, causing the space-time passage to destabilise and collapse.
As a result, they had arrived in an entirely different and unknown space-time instead of reaching their intended destination.
It was disastrous.
Karasuki had never encountered such an incomprehensible failure during space-time travel.
All it could think of was leaving this unknown space-time as quickly as possible to prevent further consequences.
The black-haired man with the Mangekyō Sharingan was Uchiha Sasuke from another space-time.
After hearing Karasuki's warning, he frowned.
"Space-time disruption? Space-time travel? An unknown space-time?"
His expression became even more serious.
"Did we return to the past?"
Judging from the Chakra signatures around him and Karasuki's explanation, he had formed a vague theory.
Had they travelled into the past?
Karasuki's voice remained urgent.
"No. This is not the past. It is another unknown space-time. I cannot determine the exact circumstances. An error occurred, one that I am unable to evaluate."
Sasuke's brow furrowed even more deeply.
They appeared to have experienced something extraordinary.
Even without Karasuki's explanation, the familiar yet strangely different Chakra signatures surrounding him were enough to make his scalp tingle.
"Huh? What? What is going on?"
The blond boy was none other than Uzumaki Boruto, the protagonist of Boruto: Naruto Next Generations.
Although he did not understand exactly what had happened, he had heard Karasuki's warning.
A mixture of astonishment and panic appeared on his face.
"What do you mean by an unknown space-time? Can you explain it properly?"
What was happening?
Boruto had only one question.
Where in the world had they ended up?
(To be continued.)