Rinnegan

The Rinnegan is characterised by a ripple-like pattern around the pupil, with a light purple iris and sclera. It is said to be the most powerful of ; the user can use all six forms of chakra nature transformation, allowing them to master any technique in a short period of time. It also allows the user to use all of the six paths techniques as well as control the seventh path - who is "beyond life and death" - to use the Outer Path: Samsara of Heavenly Life Technique.

The Six Paths of Pain were all reanimated corpses that Nagato gave the Rinnegan to through some unknown means. By doing so, Nagato could see each individual body's field of vision, coordinating the bodies with extremely precise planning. The animals summoned by the Animal Path also possessed the Rinnegan, suggesting that Nagato controlled and could see through them as well. On its own, the Rinnegan allows the user to see chakra, including otherwise hidden barriers. It can also decipher more of the Sage of the Six Paths' tablet than the Sharingan and the Mangekyō Sharingan are able to.

The first person to possess the Rinnegan was the Sage of the Six Paths. Because of the Sage's mythical status, many characters believed the Rinnegan was only a legend or a mutation. It later showed up in Nagato during his childhood. Madara Uchiha claims that he gave Nagato the Rinnegan. For this reason, he believes he is entitled to taking the Rinnegan from Nagato's body after his death. He implants one of Nagato's Rinnegan in his left socket, replacing the Sharingan he lost to blindness.

At the Fourth Shinobi World War, Madara and Kabuto awaken the dead Jinchūriki using Edo Tensei. Madara implanted all of them with 1 Sharingan and 1 Rinnegan like him.

Trivia

 * In the anime, the Rinnegan was depicted as being multicoloured in its first few appearances. Once coloured manga illustrations of the Rinnegan were released, this was corrected.
 * In Naruto: Shippūden episode 203, a silhouette of the Sage of the Six Paths is shown. Here, the Sage's Rinnegan is shown to be red instead of the usual colour.
 * is the Japanese term for Samsara, the cycle of reincarnation or rebirth in several Indian religions. This is reflected in the names of Six paths of Pain, which share the names with Samsaric realms of reincarnation.