As Minato Namikaze pondered, the battle on the surface of the lake grew ever more intense.
The Nine-Tails' chakra flooded Naruto Uzumaki's body, seizing control of both his movements and his mind as it drove him to attack Sasuke Uchiha. Long-range combat had always been Naruto's weakness, but with the Nine-Tails' seemingly endless chakra, even that shortcoming was forcibly made up for.
Crimson chakra surged outward, forming a fox claw more than ten meters long that slammed toward Sasuke. Naruto himself moved like a feral beast, dropping to all fours and sprinting across the lake's surface. Even the chakra-formed tails moved as flexibly as arms and legs.
"This isn't Naruto Uzumaki anymore. It's the Nine-Tails," Young Kakashi said.
Even from where they stood, the pressure of the fight was overwhelming.
The advantage of the three-tomoe Sharingan was immediately suppressed by the Nine-Tails' sheer power and killing intent. Unlike Naruto, the Nine-Tails had no intention of showing Sasuke any mercy. Every casual blow sent towering waves across the lake, reducing the surrounding rocks to something as fragile as clumps of soil.
"Sasuke-kun's cursed seal!" Sakura cried.
She was talking about Sasuke Uchiha, who had just been smashed from the lake's surface and sent crashing down near Hashirama Senju's feet.
Everyone watching, Sasuke, Naruto, Sakura, Obito, Kakashi, Rin, Minato Namikaze, and Young Kakashi, saw it clearly. A massive cursed seal spread across Sasuke's body.
As the Nine-Tails pressed its assault, the seal rapidly crept over him, covering him completely. Even his appearance was utterly transformed.
"So that's Orochimaru's cursed seal?!"
Sasuke stared at his other self. Setting aside how hard the transformation was to accept, there was no denying that the chakra flowing through that body had grown far stronger.
Obito, his Sharingan active as well, watched the chakra within that Sasuke and frowned. "Something's not right. This chakra feels different from the Nine-Tails in Naruto. It doesn't feel like direct control, but…"
He trailed off, unable to properly describe the sensation.
Adult Kakashi activated the other Sharingan that belonged to Obito, filling in the rest. "It's an infiltrative type of invasion. It seeps in and subtly alters that Sasuke's personality."
"Do cursed seals and cursed seal tags both have that kind of effect?" Naruto asked.
Rin nodded. "The cursed tag on my heart sometimes makes my emotions more irritable. But I'm a medical-nin, so I can stay aware of it, and Isobu helps suppress it. That's why it hasn't gotten out of hand."
If she hadn't brought it up, Naruto and Sasuke might have nearly forgotten that Rin still bore a cursed seal on her heart.
Even so, it remained a thorn lodged in the hearts of everyone on Team Minato.
Minato Namikaze spoke thoughtfully. "I've heard that Orochimaru's cursed seals are divided into the Heaven Seal and the Earth Seal. The one on Sasuke should be the Heaven Seal. Both are methods of forcibly using Senjutsu."
He reached out and patted the Sasuke beside him. "You're different from Orochimaru. You have the potential to cultivate Senjutsu properly, so don't rush to gain power through methods like that."
"Mm," Sasuke replied.
He might envy that power, but he had no intention of letting himself be controlled by some stinking snake.
They continued watching the battle between Naruto Uzumaki and Sasuke Uchiha. One fought like a wild beast, while the other…
…looked even more like a monster than a beast.
The boy who had previously been controlled by the Nine-Tails had already regained his senses. Seeing Sasuke's current state filled him with shock and pain. More than anyone, he wanted to cast off the label of "monster." He kept pushing himself, striving for recognition, longing to earn things through his own effort.
But Sasuke was different. This Sasuke was lost.
How could he so easily choose to throw away such important things, one by one?
Naruto Uzumaki couldn't understand it. After losing his family once already, did Sasuke really want to personally destroy the bonds he had only just managed to rebuild?
Naruto could see it clearly now. Sasuke was indulging in the sense of superiority that came from being a "monster," all in the name of "power."
Sasuke Uchiha even claimed that he was more "special" than Naruto.
Naruto shouted at him, "You call this special?!" Was it really worth it, selling himself to Orochimaru, the man who killed the Third Hokage and caused the deaths of countless comrades from the villages, just to be 'special'?!
Boom!!
Wrapped in the Nine-Tails' chakra, Naruto Uzumaki smashed the fully cursed-seal-transformed Sasuke Uchiha straight into the stone wall of the Valley of the End.
When the dust finally settled, what Team Kakashi and Team Minato saw next was something even harder to put into words.
A pair of grotesque giant hands burst from Sasuke Uchiha's back. The bones were twisted into strange shapes, and the nails looked like the talons of some monstrous beast…
Obito frowned.
"Webbing between the fingers… that's disgusting!"
"Shut up and watch!" Sasuke snapped impatiently.
Naruto stared at the massive hands growing behind that Sasuke. "Wouldn't that make him tip backward?"
Sasuke: "..."
Obito spoke again, adopting the tone of an elder lecturing a junior.
"Sasuke, you absolutely can't turn into something like that Sasuke Uchiha. It's way too ugly. Honestly, it's only a little better than Danzō's arm, and that's not saying much."
He knew provoking Sasuke like this was the best way to make him stay as far away as possible from cursed seal transformations.
"Didn't you hear me when I told you to shut up?!"
Sasuke's three-tomoe Sharingan glared fiercely at the overly talkative Obito.
Obito finally stopped talking, though he muttered to himself inwardly. I'm the one with the Mangekyō. What's he being so arrogant for?
Minato and Adult Kakashi stepped in to calm them both.
"Enough. Stay ready. Their fight won't last much longer," Minato Namikaze said.
"Huh? Why?!" Naruto blurted out.
He felt like that version of himself and Sasuke could easily keep fighting until nightfall.
Kakashi explained, "Don't forget, the Kurama inside that Naruto isn't the same as the one inside you. The chakra it releases corrodes his senses. Sasuke's situation isn't much better either. Prolonged use of cursed seal transformation will erode his will as well."
"That's right," Minato continued. "Senjutsu is an extremely difficult state to control. I'm not familiar with the senjutsu of the Shikkotsu Forest or Ryūchi Cave, but at Mount Myōboku, one small mistake can turn you into a stone frog forever. The Three Great Sage Regions all have their own methods. Even if it doesn't turn you into stone, losing yourself is almost guaranteed."
That information made several people who had planned to train in senjutsu after the Chūnin Exams swallow hard.
...
On the other side—
"Did you know?" Sasuke Uchiha suddenly spoke to Naruto Uzumaki while standing in the lake. "This place is called the Valley of the End. Don't you think it suits the two of us perfectly? Let's finish everything right here."
Ox–Hare–Monkey!
The shrill cry of Chidori rang out once more across the Valley of the End. Empowered by the cursed seal, the lightning turned pitch black.
Naruto opened his right hand. Wrapped in the Tailed Beast cloak, he no longer needed shadow clones to form a Rasengan.
The two leapt up beneath the towering statues of Madara Uchiha and Hashirama Senju, charging straight at each other.
"Chidori!"
"Rasengan!!"
The collision of overwhelming power erupted in a blinding flash, forcing Team Minato and Team Kakashi to avert their eyes. Even the surrounding sounds seemed to vanish, swallowed by the impact.
In the next instant, both figures were engulfed by a sphere of dark energy…
The energy sphere continued to expand, warping even the weather above as thunderclouds gathered.
The Valley of the End itself remained intact, but the waterfall crashing down from above was completely blocked by the solidified black sphere. Below, waves of lake water surged outward, flooding into the nearby forest. If Team Minato and Team Kakashi hadn't been standing in the trees, they would have been caught up in it as well.
"How are they?! What's happening to them?!" Obito shouted anxiously.
He was deeply worried about this world's Sasuke Uchiha and Naruto Uzumaki.
Sakura and Rin were already prepared to rush in and provide medical treatment at any moment.
Dark clouds filled the sky as thunder roared again and again.
No one knew when this world's Kakashi Hatake would arrive.
At that moment, Naruto and Sasuke of Team Kakashi watched their counterparts from another world, their emotions churning as they saw a completely different path unfolding before them.
Paths diverging…
This was the road Sasuke Uchiha had taken after Orochimaru planted the cursed seal within him.
In a situation like this, unless Naruto Uzumaki could hold fast to his original resolve and turn the tide by pulling Sasuke back to his side…
Sasuke Uchiha would become the second Obito Uchiha.
The Masked Man.
Madara Uchiha.
Standing against the entire world.
…
The last trace of sunlight slipped away from Naruto Uzumaki's face, while Sasuke Uchiha stood beside him.
If not for the Sharingan of Sasuke, Obito, and Kakashi still catching the flow of chakra within Naruto's body in the distance, or for Isobu and Kurama reassuring their respective hosts that Naruto Uzumaki was still alive, they would have rushed out immediately.
"No matter what, with Kurama inside him, Naruto should be fine."
Minato Namikaze said this, though it was hard to tell whether he was comforting the others or himself.
Adult Kakashi remained silent.
Even with the Sharingan, they couldn't clearly see every detail of what had happened. But Naruto lying unconscious, and the deep slash carved across Sasuke's forehead protector, a mark resembling that of a Missing-nin, made one thing clear enough…
When two evenly matched opponents faced each other, both Sasuke Uchiha and Naruto Uzumaki had resolved themselves completely.
Sasuke Uchiha's forehead protector fell to the ground as torrential rain began to pour from the sky.
Up to this point, this world's Kakashi Hatake still hadn't arrived.
"It's time to act," Minato Namikaze said.
With that order—
As the forehead protector of this world's Sasuke Uchiha dropped to the ground, and he coughed up blood from the backlash of the cursed seal before collapsing to one knee, staring at Naruto Uzumaki…
Swish—swish—swish—
Eight figures leapt down from the trees at the same time.
They appeared around the utterly exhausted Sasuke from every direction.
In his current state, Sasuke's reactions were sluggish. In the relentless rain, he stared at the unconscious Naruto, their positions oddly close. They were facing each other, their foreheads nearly touching.
"So close. Don't tell me you'll lose control and kiss him," Obito said.
He had tried to copy Young Kakashi's sharp-tongued style.
Instead, it backfired spectacularly.