"I Know" (分かってる, Wakatteru) is chapter 644 of the original Naruto manga.
Through the fist bump, father and son begin to meld the chakra of Yin and YangKurama together, and while the Shinobi Alliance members look on in desperation, Minato and Naruto employ their strategy. To everyone's shock, their Version 1 mantles soon reappear and while Sakura notes that she thought the shroud had disappeared, Katsuyu informs her that she had noticed it while healing the shinobi and realised that the shroud had only diminished, and Hinata noticing this time it wasn't only Naruto's chakra. As Jūgo, who had made his way back to Sasuke's side, notes that the situation was getting hopeless and that Sasuke needed to have him reverse summon them, Naruto calls for the two to come before him so he could distribute his chakra to them as well. While garnering praise from Hashirama for the sheer volume comparable to his own, Obito deems this a futile effort and while sealing himself away in the substance, as the tree fire the Tailed Beast Balls. As the dust settles, everyone is revealed to have survived the attack, much to Obito and the Alliance's shock. While Tobirama praises Minato coming to their aid for the second time during the battle, it is explained that by melding Yin and Yang Kurama's chakra, Minato was in turn connected to the other shinobi on the battlefield. This allowed him to teleport them outside of the barrier. Explaining the concept based off how shadow clones operated, a stumped Naruto is surprised that Tobirama knew so much about the Shadow Clone Technique, causing Tobirama to irritably exclaim that it was another technique he had invented. Naruto's later echoing of his father's sentiments, causes Yin-Kurama to note that the young jinchūriki must have had a curious upbringing to be treating a tailed beast as a comrade. Minato takes the opportunity to tell Naruto that he wished to speak to him, but Naruto dismisses him noting that men could say all they wanted to each other with a mere glance. Allaying his father's misgivings, Naruto happily notes that both his and his mother's feelings had already been conveyed to him.