Outer Path

The is the seventh path of Pain, not included with the main Six Paths of Pain. It has control over Life and Death. When used by the Naraka path, it's used for interrogation and rejuvenation.

It is used by the Naraka path for interrogation and is capable of discerning whether an individual is lying or not. When implemented on a target, a serpent-like apparition of their life force energy emerges from their mouth and presented to the figure. The Outer Path then proceeds to pass its judgment on the victim. If they are lying (or refuse to answer the question), their life force energy is consumed and they die. If the target is telling the truth, they don't die, though they're left extremely exhausted. When the Naraka path uses this technique, the figure possesses the Rinnegan eyes similar to how the Animal path's summons all possess the Rinnegan. The Outer path can only be seen by the ones it's being used upon.

As a secondary ability, the Outer Path can repair damaged or destroyed the other Paths of Pain. When it consumed the remains of the Asura path, the Path emerged from the figure fully restored and is even wearing new Akatsuki robe (the body had discarded its previous robe). While the Outer Path is being used for this, it seems that others are able to see it, unlike when it is being used for interrogation purpose. However, it was Naruto in Sage Mode that was able to see it, so it is possible that normal people cannot, even for revival.

Lastly, the Outer Path can be summoned for the Outer Path: Samsara of Heavenly Life Technique, where Nagato can release life force energy to people who were recently killed and allow their souls to return to their rejuvenated bodies. This jutsu can only be used by Nagato, the main entity in control of the Six Paths. This power is said to transcend even the very concepts of life and death.

Trivia

 * The Outer Path is based on the King of Hell, Yama, the judge of the dead in the Buddhist religion. He decided if someone stayed dead or returned to the world of the living, and would choose how they would be reincarnated. It's believed that if you lie to him, he will rip out your tongue.
 * Gedō (外道, lit. "Outer Path"), derived from the Sanskrit Tīrthika, refers to any doctrine which "treads the outer path" to enlightenment. This is opposed to the teachings of orthodox Buddhism (the "inner path"), and is thus considered misguided and heretical.
 * The black flames that surround the base of the Outer Path resemble those of the Amaterasu.