Rinne Sharingan

The is the progenitor of the Rinnegan and Sharingan. It is characterised by a ripple-like pattern which spreads over the eyeball, with red sclerae and irides, containing a pattern of nine tomoe.

Background
This dōjutsu was first manifested by Kaguya Ōtsutsuki as a third eye on her forehead after eating the Chakra Fruit of the Shinju, and later by the Ten-Tails, the combined entity of Kaguya and the Shinju. As the Ten Tails' jinchūriki, Madara Uchiha was able to awaken this dōjutsu in his own forehead by approaching the moon after regaining both of his Rinnegan. As a result of Black Zetsu's actions, Madara's body then served as a vessel for the resurrected Kaguya, who retained the Rinne Sharingan in her third eye. Once Naruto and Sasuke made physical contact with her, they activated the Six Paths — Chibaku Tensei and her third eye was closed by a horizontal eyelid under the effects of the fūinjutsu.

Abilities
The Rinne Sharingan possesses the ocular power of the Sharingan, and can be used to cast the Infinite Tsukuyomi, an extremely powerful genjutsu which can only be negated by the Rinnegan and the chakra of the nine tailed beasts. Using this dōjutsu, Kaguya can also teleport herself and others to a series of alternate dimensions.

Trivia

 * The kanji is also used in Sharingan and Rinnegan, potentially linking the three terms etymologically.
 * The Infinite Tsukuyomi, despite only being cast by the Rinne Sharingan, has been referred to by Sasuke Uchiha as a genjutsu of the Rinnegan. However, the distinction between the Rinnegan and Rinne Sharingan was made clear in the fourth databook.
 * As a reach-around for not possessing the Rinne Sharingan, Obito Uchiha attempted to cast the Infinite Tsukuyomi by manifesting the Ten-Tails' tree form outside of his body as its jinchūriki.
 * When the Ten-Tails was revived by Obito in an incomplete state, due to the Demonic Statue having absorbed only fragments of Gyūki and Kurama's chakra, its Rinne Sharingan had only six tomoe.
 * When Madara landed on ground after casting Infinite Tsukuyomi, the Rinne Sharingan on his forehead had only six tomoe. While clutching faces of Naruto and Sasuke and shedding tears, Kaguya's Rinne Sharingan also had only six tomoe.