Reunion, and Then

Wrapped in a Tobi shell and linked to Hashirama's living clone, Obito taps the power of the Demonic Statue of the Outer Path and shatters the boulder sealing one of the tunnels, drawing admiration from the original White Zetsu. Roused from rest, Madara asks if the boy means to leave. Obito voices gratitude for being saved, but Madara brushes it aside, telling him to return later and thank him properly. With Zetsu prepared to steer his clone from afar, Obito throws on a cloak and heads out. Reports reach him along the way, including the fact that Minato is absent from the group. The clone offers to fight in his place, judging Obito the weaker of the two, but Obito rejects the idea, arguing that Kakashi carries his missing Sharingan and that the two of them working together is the stronger pairing. As the clone lists the advantages of blending Senju and Uchiha cells, Obito mistakes the sensation of rain, only to spot enormous columns of water erupting from the ground where explosions have struck. Pressing on, he begins glimpsing fragments through his hollow left socket: images of Rin with a hand thrust through her chest. Dismissing them as illusions, he keeps moving, and arrives to find Kakashi's Lightning Cutter buried in Rin's heart.

Obito wields the Outer Path statue's power through Hashirama's clone and frees a sealed passage. Madara wakes and lets him depart. Obito refuses the clone's offer to substitute for him, insisting his bond with Kakashi is the better combination. Phantom flashes of Rin's death bleed through his empty eye socket. He reaches his teammates just in time to witness Kakashi's hand pierce Rin's chest.

This is chapter 604, gathered in volume 63 as part of the Fourth Shinobi World War: Climax. The scene lays the groundwork for Obito's origin, showing the exact tragedy that turns him against the world.