The Origin Sphere Space was a core realm created by Shinji through "Amenominaka," a tangible, physical domain rather than an illusion. Beyond it, he could form other extreme environments such as the Lava Prison, Frozen Mountains, Sulfuric Sea, Endless Desert, and Supergravity Space, but the Origin Sphere Space stood as the ultimate battlefield.
By dragging Boros into this realm, Shinji could fight without any concern for collateral damage. Everyone else remained in the real world, so even if Boros' Collapsing Star Roaring Cannon completely destroyed the Origin Sphere Space, it would not matter. Shinji could recreate it whenever he wished.
"Ahhhhhhh, !!" Boros roared, unleashing the Collapsing Star Roaring Cannon directly at Shinji. Even when he realized the space around them had suddenly shifted, the energy already released could not be recalled. His aim was no longer planetary destruction, but defeating Shinji himself.
As the devastating blast surged forward, Shinji, in his Ten-Tails form, expanded the Truth-Seeking Ball to an immense scale. The sphere continued to grow until it far surpassed the Collapsing Star Roaring Cannon in size, appearing like a black miniature planet.
When it reached its limit, it became the Final Truth-Seeking Ball, a power capable of erasing all things and returning the world to pure nothingness.
At that moment, Shinji wielded not only the might of Kaguya Otsutsuki but also the collective energy of billions of people from across the globe. Every fragment of that strength was condensed into the Final Truth-Seeking Ball.
The two overwhelming forces collided, their energies twisting and grinding against each other. After a tense instant, the Final Truth-Seeking Ball consumed the Collapsing Star Roaring Cannon entirely, setting off an explosion strong enough to obliterate the entire Origin Sphere Space. In a single moment, everything within was reduced to nothing.
…
[Alert! The host has defeated the cosmic overlord Boros. Reward: 500 points!]
The aftermath left the Origin Sphere Space in ruins. Boros lay in the fragmented void, reduced to his head and part of his upper torso, his body shriveled like a dried husk. The Collapsing Star Roaring Cannon had drained every last trace of his strength, leaving only a few shallow breaths and no ability to regenerate.
Shinji's state was not much better. While forming the Truth-Seeking Ball, he had been unable to shift into an intangible state, and the clash between the Final Truth-Seeking Ball and the Collapsing Star Roaring Cannon occurred in an instant. If he had phased at that precise moment, the Final Truth-Seeking Ball would have phased with him. Although he could still have won afterward, since Boros would have been left powerless after firing his cannon, that was not the kind of victory he sought. He chose instead to confront Boros head-on.
At the very least, he still had Izanagi as an unbeatable safeguard.
Now lying on the ground, Shinji was missing his left arm and right leg, his body torn and drenched in blood. Even so, he was in slightly better shape than Boros.
"I… lost…?" Boros' voice was faint, but he clung to a sliver of consciousness, able to sense that Shinji's life force still lingered.
"Probably. I'm not exactly fine myself… cough, cough…" Shinji replied before spitting out a mouthful of blood.
"I see… so the prophecy was right. This truly was an evenly matched battle…"
Realizing Shinji was also in terrible shape, Boros felt a sense of peace wash over him.
"Yeah…" Shinji replied softly, offering no further words.
He had already begun casting his technique. In his only remaining right eye, a single Sharingan with three tomoe appeared, its crimson glow steady and cold.
"Thanks… you've helped me fulfill my wish…" Boros forced the words out with the last of his breath. "If there's a chance… let's fight again in the next life…"
It was clear he had accepted his death. Though defeated, it had been after a fierce and equal struggle. This was exactly the kind of battle he had longed for, one fought against a true equal. To die this way left no regrets.
"Ugh!" Boros suddenly coughed up a mouthful of blood, his life hanging by a thread.
Izanagi.
At that instant, Shinji sacrificed the three-tomoe Sharingan in his right eye to activate the forbidden technique. Reality itself was rewritten, erasing the fact that he had been grievously injured and restoring his body to perfect condition in a heartbeat.
Even without Izanagi, he would not have truly died, for Kaguya's power had rendered him immortal. Only someone like Saitama could completely overwhelm him. But Izanagi gave him immediate recovery, allowing him to act before Boros drew his final breath. Without it, his wounds would have taken time to heal, and Boros would have already been lost.
"What nonsense are you talking about? We still have a chance to fight in this life, why wait for the next?"
With his strength renewed, Shinji teleported to Boros' side. Dropping to one knee, he placed a hand on Boros' chest, channeling the energy needed to restart his regeneration.
Boros, who had been moments away from death, was abruptly pulled back from the brink. The surge of energy sparked his recovery, and his body began rapidly repairing itself. His vision cleared, and his breath steadied.
"…" He gazed at Shinji in silence, taking in his completely restored condition.
"Don't look at me like that. I almost died just now too, I just have a way to return," Shinji said evenly.
"…So in the end, that prophecy was unreliable," Boros murmured after a long pause.
"Come on. This space is collapsing," Shinji replied.
With that, he took hold of Boros and left the Origin Sphere Space.
…
Because Shinji had drawn Boros into the Origin Sphere Space, the collision between the End Truth-Seeking Orbs and the Collapsing Star Roaring Cannon had occurred entirely within that dimension, sparing the real world from destruction.
The spaceship and its power core remained intact, but the core's energy came from Boros himself. Having poured nearly all of it into the Collapsing Star Roaring Cannon, what little remained was not enough to sustain the vessel. The ship now trembled violently, threatening to tear itself apart.
"Is it over? Why did Shinji and that alien just vanish?"
"Maybe they shifted the battlefield. If that last attack had gone off here, we'd all be dead."
"The ship above us is shaking hard. Is it about to crash? That would mean the fight's done…"
"Probably. What a terrifying battle… no wonder Madam Shibabawa made such a prophecy."
By now, Bang and the others cared little about the exact outcome of Shinji's fight with Boros.
They had no idea that although Shinji had saved Boros in time, the alien's power was almost entirely gone.
It was similar to Black Sperm after the Monster Association war, reduced to a single cell, except Boros was still vastly stronger, at least retaining his incredible physical strength.