Wind Release: Rasengan

The Wind Release: Rasengan is an original technique created by Naruto Uzumaki.

Overview
Minato Namikaze created the Rasengan with the intention of combining it with his own nature, a task that proved too difficult for him to complete prior to his death. Kakashi Hatake also failed to combine the Rasengan with his own lightning-nature, causing him to invent the Chidori instead. Naruto initially struggles to combine the Rasengan with his wind-nature despite using shadow clones, which he describes as needing to look left and right at the same time. He is eventually able to overcome this obstacle by having one clone shape the chakra into a sphere, and have another clone infuse the sphere with wind-nature. The end product becomes the Wind Release: Rasengan. If the user can properly perform a Rasengan, they require only one shadow clone to create aid in infusing the wind-nature. After completing this technique, it is possible for one to perform this technique without the aid of shadow clones and in the conventional one-handed style.

The Wind Release: Rasengan appears largely identical to the standard Rasengan, though it's shown to be stronger. When used in combination with other jutsu, as in the case of the Typhoon Water Vortex Technique, its wind nature can expand the other jutsu's coverage area. Naruto invents the Wind Release: Rasenshuriken shortly after he figures out the principles of the Wind Release: Rasengan, and for that reason he rarely uses the Wind Release: Rasengan.

Tailed Beast Influence
In the Sasuke Shinden novel, Naruto uses the power of the Nine-Tails to form a Wind Release: Rasengan that he's able to throw; he also doesn't need any shadow clones to create it. When it hits its target, it creates a shockwave of wind away from Naruto. In the anime, Naruto instead uses "Rasengan: Flash".

Trivia

 * In the anime, Asura Ōtsutsuki developed Amenomihashira, a precursor to this technique.
 * While normally this technique can only be performed as handheld, in the anime, Boruto Uzumaki was instinctively able to expand on its nature to launch it as a projectile. Moreover, his version sports rings around central sphere as opposed to shuriken blades, similar to Spiralling Ring.This is likely due to his subconscious infusing of Lightning nature as well, thus technically making it a new nature transformation.