Demon Fox Rasengan

Naruto forms the Rasengan while in his one-tailed form. He uses the Nine-Tailed Demon Fox's chakra shield as a shell and molds his chakra within it, allowing him to create a Rasengan without the need for shadow clones. In the anime, this Rasengan is blue with a red outer shell, giving it a more purplish color. In the second movie, the Rasengan is orange and the various video games, the Rasengan is red. It is also much more powerful than the usual Rasengan, due to the Nine-Tails' chakra.

Trivia

 * In Naruto: Path of the Ninja 2, this jutsu is also called "Ultimate Rasengan".