Breakthrough

The battlefield blazes after the scorch-and-black-flame assault, and Naruto and Sasuke wait to see whether it connected. Tobirama flickers to Minato's side and confirms they struck before Obito could raise his mysterious orbs, yet Obito strides out untouched as those Truth-Seeking Balls consume the Amaterasu fire. Studying the situation, Tobirama notes Minato's arm has failed to regrow and concludes Obito is drawing on Yin and Yang power, which cancels the healing granted by the reincarnation technique.

Naruto's tailed-beast mantle winks out when he charges in without thinking, earning a sharp rebuke from Tobirama. To everyone's surprise Gamakichi hits Obito with a Starch Syrup Gun before his summoning fades, wanting one attempt before he vanishes. Minato and Obito argue over what the office of Hokage should mean, with Naruto warning the jinchuriki not to belittle a title he could never earn. As Naruto forms a Rasengan, Tobirama teleports him above Obito and drives the sphere into his back, proving that senjutsu can pierce this form. Minato marvels that his son has become a sage like Jiraiya, while the Yin half of Kurama reflects that Naruto grew into someone who loved his parents and won over its Yang counterpart.

This is chapter 642, collected in volume 67 within the Birth of the Ten-Tails' Jinchuriki arc, with Viz titling it An Opening. It ran in Japan across 2013 issues 37 and 38, dated September 2.