Tobirama ran and ran, a careless dash through the forest floor as he rushed to where Itama's too-small ball of chakra was, to where the distinctly bigger and flaring, flame-like chakra overshadowed his.

He wouldn't make it in time. He knew that, but he still pushed his body to move faster, because he thought Itama would already be dead by now.

He and Hashirama had left camp the moment after Itama's team returned without him and explained they'd been separated, that the Uchiha had signaled out Itama in an ambush and forced him deeper into Uchiha territory and away from them.

Five adult Uchiha against his brother. Another pointless death, just as Hashirama said. An honorable death, their father would claim.

Tobirama's stomach curled.

Hashirama had gone to search the Uchiha border territories to the north, while Tobirama had sped west.

And Itama, somehow, was still alive. Tobirama leapt forward over a gnarled root and into a clearing, sliding to a stop and jerking his blade out to aim at his opponent in the same motion.

But he stopped upon seeing Itama.

Itama was sitting on the floor against a large boulder, a black-clad figure folded over the top of it. His brother stood quickly upon seeing him, his chakra low, but not as low as he would've expected after being battered by five Uchiha, and looking relatively unharmed for having been in Uchiha territory alone for over three hours.

Tobirama didn't understand. He understood even less as Itama tapped the hanging, limp foot of the pre-teen, and the pre-teen sat up. Tobirama's eyes widened in alarm at the visible sharingan as the pre-teen rubbed his eyes, and his body moved without another thought.

"Away from him, Itama!" he yelled, leaping up to get high enough to strike at him, and it alarmed him even more when the pre-teen only gazed sleepily at him.

"Tobi, wait!" Itama said, holding out his arms in defense of the Uchiha, and it made him hesitate for a brief moment and land in front of his brother, because his chakra didn't feel disrupted like it would be if he were in a genjutsu.

Still, Tobirama grabbed his brother by the shoulder and made the release seal. "Kai!" he shouted.

Itama blinked at him, but his chakra didn't change. It made even less sense.

He paused, still holding the seal, but he couldn't wrap his head around why his brother would willingly be in Uchiha territory with an Uchiha.

"He saved me," Itama quickly explained, grabbing his arm. "I was surrounded and—and he stopped them from killing me!"

Tobirama stared blankly at him, then lifted his gaze to the Uchiha staring down at them, sitting casually just above them with his legs hanging down and his pants rolled up practically to his knees.

"Why?" Tobirama asked, his voice steel. "You're an Uchiha. Why would you stop your clansmen?"

"You talk formally for being so young," the Uchiha said. "Tobirama Senju."

Goosebumps prickled along his skin. He shoved Itama behind him and brandished his blade at the Uchiha. But the Uchiha didn't look threatened at all.

"Have your brother explain it to you," he said with a yawn. "I don't have much more time. But since I didn't hear you fighting anyone on the way here, everyone must've gone home."

The ability to stop his clansmen, the casual, but powerful air about him, his knowledge...

Tobirama took a step back. "Sunless Asahi," he named his enemy.

Heir to the Uchiha clan, a prodigious talent, son of Tajima the Butcher, and the second-greatest threat within that clan as a whole.