Naruto, while in Nine-Tails Chakra Mode, uses a chakra arm to form multiple Rasengan above his head. He then uses additional arms to hold the Rasengan and hit multiple opponents simultaneously. Naruto is also capable of using this technique in Tailed Beast Mode, creating a giant Rasengan right in each tail. He can wield them by himself, or let his friends handle each Rasengan.
Part of this technique was shown on the cover of chapter 515, thirty chapters before its proper début.