"Kakashi Chronicles ~ Boys' Life on the Battlefield ~ Part 2" (カカシ外伝～戦場のボーイズライフ～前編, Kakashi Gaiden ~ Senjō no Bōizuraifu ~ Kōhen) is episode 120 of the Naruto: Shippūden anime.
As Kakashi heads through the woods to Kannabi Bridge, he flinches in pain from his wound. Recalling Rin healing his wounds and Obito's steadfast decision to abandon the mission to save her, Kakashi begins to consider his choices. Meanwhile, Obito manages to locate the two Iwa-nin outside their cave. As he slaps his face in order to focus, the sound carries throughout the cave, alerting the ninja to his presence. Taiseki decides to deal with Obito while Kakkō continues using his Interrogation Genjutsu on Rin in an attempt to break her. Using his Hiding with Camouflage Technique, Taiseki sneaks up on Obito and prepares to kill him with a kunai, only for Kakashi to interfere and slash at Taiseki with his White Light Chakra Sabre. Seeing the sabre and the white hair, he wonders whether Kakashi is the Konoha's famed "White Fang", only to realise that he is just his son. As Obito questions why Kakashi would come and save him, Taiseki uses his camouflage technique once more and sneaks up on Obito; Kakashi attempts to save him but ends up getting his left eye slashed. As Kakashi reels in pain, Taiseki rushes towards Obito, only for Obito to turn around and stab him with a kunai. Kakashi and Taiseki wonder how Obito was able to see the latter, and Obito realises that he has finally awoken his Sharingan. Using the med-kit given by Rin, Kakashi bandages his left eye and the two head inside the cave to save Rin.
Inside the cave, Obito is able to use his Sharingan to keep up with Kakashi and avoid being struck by Kakkō, and the duo manage to defeat him. As they rush to free Rin, Kakkō uses the opportunity to cause a cave-in. As Team Minato attempt to run out of the cave, Kakashi is struck by a falling rock. Obito picks Kakashi up and notices a big boulder above their head, and throws Kakashi out of the way, taking the brunt of the boulder's impact on himself. As Kakashi and Rin come to, they discover Obito pinned underneath the boulder, the entire left side of his body crushed. Kakashi begins to cry, as he believes he could have prevented this had he chosen to follow Obito at the beginning and that it did not matter that he was jōnin and thus captain of the team. Remembering that he had not given Kakashi a gift for his promotion, he asks Rin to transplant his left Sharingan into Kakashi's left eye socket. With the transplant completed, Kakashi rushes outside the cave and uses his White Light Chakra Sabre to attack Kakkō. As Kakkō destroys the blade, Kakashi uses his Chidori to strike the Iwa-nin and kills him. As the other Iwa-nin arrive, one of them uses his Earth Release: Tearing Earth Turning Palm cause the entire cave to collapse; Kakashi escapes with Rin as Obito is buried in the rubble, where he muses in his last moments that he is saddened to die right when he and Kakashi had finally begun to get along and that he never told Rin that he loved her. Outside, Kakashi and Rin are ambushed by the surrounding Iwa-nin, and Kakashi tells Rin to flee while he fights them off, as he had promised Obito that he would protect Rin with his life. Kakashi tells Rin that Obito had loved her and that she was everything to him, as Rin attempts to tell Kakashi that she has feelings for him. As Kakashi prepares his Chidori, they are saved by the arrival of Minato, who uses his Flying Thunder God Technique to defeat all of their enemies.
As he comes to, Kakashi asks how Minato had arrived to save them and Minato reveals that the marking on the Flying Thunder God Kunai he had given Kakashi allows him to teleport to that location; he also adds that Rin had told him what had transpired. Following the destruction of the Kannabi Bridge, the Third Hokage declared that two heroes were born that day, each with their own Sharingan. Obito had received his own memorial as a shinobi who had died during the Third Shinobi World War while Kakashi earned the moniker "Kakashi of the Sharingan".
- This episode aired alongside episode 119.
|Role||Seiyū||English Voice Actor|
|Kakashi Hatake||Kazuhiko Inoue||井上 和彦||Inoue Kazuhiko||Dave Wittenberg|
|Obito Uchiha||Sosuke Komori||小森 創介||Komori Sōsuke||Vic Mignogna|
|Rin||Haruhi Terada||寺田 はるひ||Terada Haruhi||Stephanie Sheh|
|Minato Namikaze||Toshiyuki Morikawa||森川 智之||Morikawa Toshiyuki||Tony Oliver|
|Narration||Hidekatsu Shibata||柴田 秀勝||Shibata Hidekatsu||Steve Kramer|
|Iwa-nin Kakkō||Tomoyuki Shimura||志村 知幸||Shimura Tomoyuki||Henry Dittman|
|Iwa-nin Taiseki||Kanji Suzumori||鈴森 勘司||Suzumori Kanji||Kirk Thornton|
|Konoha shinobi||Kenichiro Matsuda|