Madara's eyes showed a hint of bewilderment.
Hashirama sighed inwardly. It was because he, as Madara's closest friend, had failed to find a way to fill the emptiness in Madara's heart sooner that Madara had become trapped in the Moon's Eye deception Black Zetsu had woven into the Uchiha Stone Monument.
Madara had grown more and more extreme afterward. So much so that when Tobirama said he was no longer suited to become the Hokage who decided the village's future, Hashirama had actually hesitated, leaning toward agreement.
So...
Hashirama understood. Rather than being disappointed in Konohagakure or the Ninja World, Madara had been disappointed in him, his dearest friend.
After a moment of silence, Izuna suddenly asked Tobirama, "How did you die?"
"During the First Shinobi World War, I led six students to Kumogakure in the Land of Lightning to negotiate a ceasefire. On the way, we encountered Kumo Village rebels, the Gold and Silver Brothers, who had eaten the Nine-Tails' chakra. They killed the Raikage. To ensure my students could bring the agreement back, I made the correct choice."
The so-called correct choice was for him to go alone as bait, buying time for his students to escape.
"Getting killed by nameless nobodies only proves you were too weak."
Madara Uchiha spoke. Back in the underground tunnel, when he heard the news of Hashirama's death and Tobirama's death, he had merely sighed again at how fragile life was.
"At least I died without regret or confusion."
Madara Uchiha snorted. "Hmph. Still as sharp-tongued as ever."
Several more days seemed to pass in the outside world. Young Madara Uchiha and young Hashirama were about to reach the day of their parting.
The pebbles skipping across the water were carved with the words [Run!] and [It's a trap!]
The two quickly left, while two figures brushed past them.
The Uchiha and Senju clansmen recognized them. They were their clan heads, and Madara's and Hashirama's last younger brothers.
The four sides faced off.
Watching from Kamui's Dimension, Naruto and the others, along with the five Uchiha brothers and the four Senju brothers, could not help swallowing nervously.
"It seems we had the same idea, Butsuma Senju."
"And Tobirama is here too."
"In that case, Tajima Uchiha."
"Izuna is here too."
After the four exchanged brief greetings, they immediately began fighting. Inside Obito's Kamui's Dimension, young Madara and young Hashirama stared with wide eyes! If the war between the two clans could not truly be stopped...
Butsuma Senju and Tajima Uchiha feinted at the same time, then hurled their weapons at the second sons of the opposing clans!
"Tobirama!"
"Izuna!"
Needless to say, young Hashirama and young Madara outside Kamui's Dimension panicked.
Even the brothers inside Kamui's Dimension were startled by this dangerous scene.
Izuna Uchiha remembered that this was the moment his older brother had awakened his Sharingan. Because he severed ties with Hashirama Senju, he sealed away his emotions from that day forward. Whenever they met on the battlefield after that, they were only enemies.
Minato Namikaze seemed to have predicted everything. Much earlier, he had already split off a shadow clone and sent it to young Obito, reminding him to throw the Second Hokage and Izuna Uchiha out of Kamui's Dimension together at exactly the right moment.
And so...
The history of a certain parallel world changed once again at this moment!
Originally, the stones in young Hashirama's and young Madara's hands, the symbols of their friendship, would have knocked away the weapons flying toward young Tobirama and young Izuna.
But at this very moment!
The Second Hokage, Tobirama Senju, known throughout the Ninja World as the God of Speed, appeared!
He threw a Flying Thunder God kunai even faster, knocking away the kunai aimed at young Izuna's head. At the same time, he activated the Flying Thunder God mark and reverse-summoned himself above Izuna Uchiha, catching both the Flying Thunder God kunai and the pebble carved with [Run!] that young Madara Uchiha had thrown!
Acting at the same time as him was Izuna Uchiha.
Although he did not have a title like the God of Speed.
The Mangekyō Sharingan Izuna Uchiha awakened after being gravely wounded by Tobirama Senju back then had the ability to control the flow of time within a domain, countering speed itself.
Just as Tajima Uchiha's short blade stabbed toward young Tobirama, while young Tobirama was facing off against young Izuna across from him and had no idea what was happening, Izuna Uchiha was sent out of Kamui's Dimension by young Obito and appeared in midair. His Mangekyō Sharingan slowed the flow of time around him until it was almost frozen.
Because the slowed flow of time had no effect on him, Izuna Uchiha could leisurely move above young Tobirama and make use of both his father's short blade and the pebble thrown by that deceptively innocent Hashirama Senju.
[It's a trap!]
That was the warning his older brother had written for Hashirama Senju.
To keep Hashirama Senju alive, his older brother had not hesitated to defy their father's orders, making a decision almost equivalent to betraying the clan.
Izuna Uchiha looked at the pebble in his hand. On it was his older brother's handwriting.
When he was young and had been protected by his older brother, he had not yet awakened his Sharingan.
He did not know what awakening the Sharingan meant for the Uchiha Clan beyond gaining powerful strength.
Only when Izuna first opened his Mangekyō Sharingan and looked back did he understand what his younger brother Myoko, and later his older brother Madara Uchiha, had gone through.
What kind of pain had it taken for his older brother to awaken his eyes back then?
That meant...
For his older brother...
Parting from Hashirama Senju had been a pain he could not bear.
That pain caused the Uchiha brain to secrete a special chakra, stimulating the optic nerves and producing the scarlet Sharingan.
And even while enduring that pain, his older brother had not hesitated for a single moment to stand on his side, the side of his younger brother. Like Hashirama Senju, he had sworn to protect his last remaining brother at any cost.
And now, after receiving more information, after seeing the joy his older brother felt when he was with Hashirama Senju and hearing the vow they made atop the cliff, Izuna finally understood that the pain of separation was not simply between friends who got along. It was a one-of-a-kind mutual understanding. In Hashirama Senju's words, it was probably a revelation the heavens had given to them both.
A revelation meant for each other.
They were both young ninjas.
They had both watched their younger brothers be buried in their clans' graveyards.
They had both thought about how to stop the endless wars between ninja clans, how to stop hatred from giving birth to new hatred.
They had both resolved to protect their last remaining younger brother at any cost.
Watching Tobirama Senju catch the stone thrown by Hashirama Senju and protect the younger version of himself in this parallel world, Izuna Uchiha remembered what Tobirama had said to him not long ago.
"If you had understood Madara even a little more, you would not have stopped him from allying with my eldest brother back then, and you certainly would not have placed the Mangekyō Sharingan and the burden of the entire clan's responsibility on his shoulders alone."
The Mangekyō Sharingan stopped spinning, and time within the surrounding domain returned to normal.
Butsuma Senju and Tajima Uchiha retreated, both landing on the surface of the river.
"Who are you?!"
"Uchiha?!!"
From Butsuma Senju's position, he could clearly see that the man standing in front of his son Tobirama wore a deep navy blue, high-collared Uchiha clan robe. The red-and-white fan pattern on his back was unmistakably that of the Uchiha Clan.
From Tajima Uchiha's position, he could also see the back of the white-haired man who had saved his son. Since the man bore no clan emblem, Tajima could not immediately tell why he had saved his son.
Swish, swish.
Young Hashirama and young Madara each leapt back onto the river, standing opposite each other.
Looking at the red-and-white fan pattern ahead, young Hashirama was just as astonished as his father.
"Why..."
"Why would someone from the Uchiha Clan save Tobirama?"
Likewise, young Madara stared at the white-haired back of the head in front of him.
"No matter which clan you're from, thank you for saving my younger brother."
Tobirama and Izuna turned around at the same time.
Those faces, which looked so much like the people they had saved, made Butsuma Senju, young Hashirama, Tajima Uchiha, and young Madara all widen their eyes in shock.
Of course, the ones whose eyes widened the most, and who found it the most unbelievable, were young Izuna and young Tobirama, the ones who had been protected.
The person who saved young Tobirama really did look far too much like Izuna, while the person who saved young Izuna looked far too much like Tobirama.
Everyone present was completely dumbfounded.
"Dad..."
Young Hashirama spoke up.
"Hm?"
"Tobirama is my only surviving younger brother, right?"
This question stunned not only Butsuma Senju, but also Izuna Uchiha, who was standing in front of him and young Tobirama.
"Why are you bringing that up at a time like this?"
Without even thinking, Butsuma Senju warned his eldest son not to change the subject.
Little did he know, that answer caused young Hashirama to misunderstand.
"So that man really is Tobirama's biological father?!!"
Forgive the child. He had no idea what time travel was, so this was the only explanation he could think of.
Inside Kamui's Dimension, Team Minato and Team Kakashi nearly died laughing as they watched what was happening outside. Naruto and Obito laughed especially hard.
The five Uchiha brothers selectively ignored the fact that they had thought the same thing when they saw the adult Izuna, and the looks they gave the Senju brothers seemed to say, Are you people stupid or what?
Standing on the rooftop terrace of the Hokage Tower, the Senju Clan wanted nothing more than to crawl into a hole under the indescribable looks the Uchiha Clan beside them were giving them.
"Hahahahaha, sorry, sorry."
Hashirama scratched his head and laughed sheepishly. "I guess I've always felt Tobirama was too fair-skinned to look like a child born from a rough man like Dad, so..."
"Anyway, ahahahaha."
This time, Butsuma Senju truly could not endure it anymore.
He turned back and punched the First Hokage squarely in the face. A solid blow of paternal love sent the God of Shinobi flying a full meter.
Madara Uchiha:
Karma really does come around.
Inside Kamui's Dimension, after hearing that, young Madara, whose thoughts had been led astray by young Hashirama, also asked his father:
"Father! Could Izuna also be..."
"Madara, have you known that idiot across from you for so long that your brain has turned into wood too?"
"Ah, sorry, Father. I shouldn't have doubted you."
Doubted that Mother had cuckolded you.
"Pfft."