Naruto: High Stats in the Left Eye, Powerful Mechanics in the Right

At the start of Konoha’s founding, Madara Uchiha left the village because he and the others disagreed on their ideals. Before leaving, he called on his clan, but not a single Uchiha answered him.

Heartbroken, he left Konoha through the front gate, only to see his younger brother not far from it.

Uchiha Izumi.

Madara’s face lit up with a relieved smile. At least this last brother was still with him.

"Izumi, you really are different from those other Uchiha. Are you ready to leave with me?"

"Brother, has no one ever told you that a rogue ninja shouldn’t leave through the front gate?"

"Besides, I have no intention of leaving with you. Your way is wrong. Hashirama Senju is wrong too, and so is this world."

Madara looked at his younger brother and fell silent for a moment. Then a smile suddenly appeared on his face.

"You’ve grown, Izumi. Then prove it to me, your way. I’m looking forward to it!"

With that, Madara left Konoha.

Uchiha Izumi watched Madara’s retreating figure as the tomoe in his eyes began to spin rapidly.

Many years later, Uchiha Izumi stood atop all the daimyo, gazing at the surrounding Allied Shinobi Forces and at Madara Uchiha and Hashirama Senju, who stood at their forefront. He smiled.

"Brother, now prove it to me. Do you have the caliber to uphold the values of this flawed world?"

As his words fell, the countless Uchiha standing behind him all awakened their own Mangekyō Sharingan!

(The protagonist is a pure-blooded Uchiha, without a doubt.)