Naruto: Shippūden (2007)

S4E76 The Next Step

Kakashi admits that although he can perform the Rasengan, he’s unable to fuse it with his lightning chakra. He mentions that even the Fourth Hokage, the creator of the technique, struggled to combine it with his own elemental energy, but believes Naruto might succeed. Meanwhile, Asuma informs the other teams about Akatsuki's whereabouts, continuing on despite his worries about their power. Kakuzu hands over Chiriku’s lifeless body, ignoring Hidan's protests, and explains that he partners with Hidan because he can't bring himself to eliminate him. As Naruto trains, he becomes overwhelmed and slips into the Nine-Tails' "Demon Fox's Cloak," but Yamato quickly intervenes to suppress it.