With an angry roar from Uzumaki Naruto, a massive, glowing red Chakra orb slammed straight down onto Orochimaru's head!
Senju Tobirama: "How can that Rasengan be so huge?"
Namikaze Minato: "Lord Second Hokage, the Rasengan is a Jutsu whose size increases depending on how much Chakra the user releases. In other words, the more Chakra, the larger the Rasengan, and the greater the destructive power!"
Chapter 59