What is it?

Rinnegan (輪廻眼 lit. Wheel Cycle Eye) is exactly what the name implies; it is the dojutsu that has ripples spreads over the eyeball, regardless of its colour. Sasuke had purple Rinnegan, Momoshiki had yellow Rinnegan, and Urashiki had red Rinnegan.

Some Rinnegan, however, have Sharingan tomoe on their innermost rings, such as that of Sasuke, Urashiki and Kaguya. These Rinnegan are also known as Rinne Sharingan (輪廻写輪眼 lit. Wheel Cycle Copy Wheel Eye).

Naruto Wiki does not consider Sasuke's and Urashiki's eye as the Rinne Sharingan, which is absolutely wrong. All Rinne Sharingan are by definition Rinnegan as well. Not only Sasuke's eye is referred to as the Rinnegan, even Kaguya's eye was called the Rinnegan by Sasuke.

The Infinite Tsukuyomi is a Rinne Sharingan technique that is not present in other Rinnegan. Hence, the correct statement should be "Rinne Sharingan Genjutsu can be dealt with using a Rinne Sharingan".

It is because Obito's body was possessed by Black Zetsu when Infinite Tsukuyomi was active, and Black Zetsu is an undead who is unaffected by it like the Edo Tensei reanimations.

However, while the Infinite Tsukuyomi was cast by a red Rinne Sharingan, the victims' eyes had a purple tomoe-less Rinnegan look after they are trapped in the official coloured manga. This might suggest that the Jutsu was complemented by Madara's two other eyes similar to how the Byakugan was said to complement Kaguya's Infinite Tsukuyomi. However in the anime, the victims of Kaguya's Infinite Tsukuyomi also had eyes with a purple tomoe-less Rinnegan look, despite Kaguya herself having no such Dojutsu.

How to Acquire & Use

There are a few conditions to be met before one awakens the Rinnegan. The most known one would be Hagoromo's Chakra. Now many people got confused here as to what Hagoromo's Chakra refers to. Some call it the "Sage of Six Paths" Chakra, which is ambiguous at best and wrong at worse. At best, it can be used to refer to two different types of chakra:

• Six Paths Chakra. This is the chakra that Hagoromo's body possess naturally at birth. Both Naruto and Sasuke possess this chakra after meeting with Hagoromo. This is the chakra derived when you mix Indra's and Ashura's Chakra.
• Six Paths Sage Chakra. This is the blend of chakra of Six Paths Chakra mixed with Senjutsu Chakra. Hagoromo only has this chakra when he awakens Senjutsu himself later in his life. This is possessed by Naruto but not by Sasuke.

While Hagoromo is in fact the Sage of Six Paths, his alias isn't interchangeable with his name in this context. Because in Japanese, Six Paths Sage Chakra and Sage of Six Paths Chakra both translates to "Rikudou Sennin" Chakra, which is not what we are referring to when we talk about Hagoromo's Chakra. So for clarity, I'm going to use only the two terms in bold.

The lesser known conditions to awaken the Rinnegan is the Eternal Mangekyo Sharingan (Sage's Eyes) and the Senju or Uzumaki Cells (Sage's Body). Unlike Chakra, which has to be that of the respective transmigrants, the EMS and the Cells can be that of any member of the clan, though not all of the Senju or Uzumaki clan's body is applicable, just like not all of the Uchiha has the EMS. Only those that possess strong life force (such as Nagato) can wield the Rinnegan.

Without Six Paths Chakra, one could not awaken the Rinnegan, but might still be able to use a transplanted Rinnegan, as long as they have both the Senju or Uzumaki cells as well. Since Obito only had half of his body being made up of Hashirama's Cells, he was only able to implant and use one Rinnegan. Due to insufficient life force, implanting the second Rinnegan will cause him to lose himself.

However, in order to awaken the Rinne Sharingan instead of just a Rinnegan, one must still have the Tailed Beasts chakra in order to awaken.

This is supported by a few things. Madara said that the God Tree require all of the Tailed Beasts chakra to bloom for the Infinite Tsukuyomi, for which the Rinne Sharingan is the bud of the flower.

Secondly, in order to counter the Rinne Sharingan Dojutsu, it has to be done with both the Tailed Beasts chakra and the Rinnegan, which is likely how Hagoromo was able to release those trapped in the very first Tsukuyomi. The reason why Hagoromo didn't awaken the Rinnegan himself is because he didn't have the Tailed Beasts chakra during his awakening.

How Sasuke awakens the Rinne Sharingan is probably a workaround trick by Hagoromo by using the power of Tailed Beasts.

Six Paths Techniques

To understand what Six Paths Techniques are we first have to understand what is "Six Paths". Unknown to people its actually been used to refer to two very different things:

1. The literal six paths, that is, Deva Path, Asura Path, Human Path, Animal Path, Preta Path and Naraka Path. This can refer to the Jutsu families or individuals created by Nagato's Outer Path Jutsu. This is usually under the context involving Pain. e.g. Six Paths of Pain, Six Paths Techniques, Third Six Paths
2. The underlying principle "Six Paths" as a single term. This is usually under the context involving Hagoromo. e.g. Sage of Six Paths, Six Paths Senjutsu, Six Paths Power, Six Paths Chakra, Six Paths Chibaku Tensei.

The most clear example comes from the difference between Chibaku Tensei and Six Paths Chibaku Tensei. The regular Chibaku Tensei is already a Deva Path technique and hence part of the Six Paths technique. However the "Six Paths" in Six Paths Chibaku Tensei isn't the same as that. It is the second point which involves not just the Rinnegan but the power of both Indra and Ashura.

As you can see this can be very confusing. Six Paths of Pain, as straightforward as it may sound, refers to neither the techniques nor the individuals. It refers to the Outer Path technique that create and manipulate six bodies. This need not refer to the bodies of Pain created by Nagato, it can also refer to the bodies created by Obito, which were not called Pain, but the technique's name retains regardless. If this isn't bad enough, in some games the technique was called Rinne Six Paths, which is an even more confusing name.

Overall the naming system is just messy and confusing. To make this simple, specify what you are talking about with [Context] Six Paths [Topic]. For example, Pain's Six Paths Jutsu, or Hagoromo's Six Paths Power.

A big misconception is that having any one Rinnegan gives you ability to use all of the Six Paths Techniques. However, not a single Naruto character have shown to be capable of all Six Paths with just one Rinnegan.

To make things worse, none of the six paths were used by both a right-Rinnegan-only user and a left-Rinnegan-only user. Except for the Outer Path, which had been use by both Madara with the right Rinnegan only and Obito with the left Rinnegan only. This lets me to conclude two things:

1. Outer Path technique can be used with either left or right Rinnegan
2. The Left Rinnegan is responsible for 3 paths (Deva, Preta, Human) and the Right Rinnegan is responsible for the other 3 paths (Animal, Asura, Naraka)
3. Only when one has awakened both Rinnegan, then it's capable of unique abilities like Limbo.

Nagato is also called the Third Six Paths (三人目の六道, Sanninme no Rikudō), which was wrongly translated by some scans as the Third Sage of Six Paths. The difference is big as the former refers to the Six Paths of Pain, while the latter refers to the real Six Paths.

Hagoromo and Madara was known as the First and Second Six Paths. However, neither Obito nor Sasuke has been known as the Fourth or Fifth Six Paths. This supports the idea that one does not have all Six Paths with just one Rinnegan.

Colour of the Eye

Not all Rinnegan is capable of Six Paths Techniques. Kaguya as a red Rinnegan user has never been shown or stated to possess the "power of Rinnegan", despite being stated to possess the power of Sharingan and Byakugan.

The three abilities of her third eye (Amenominaka, Yomotsu Hirasaka and Infinite Tsukuyomi) are not part of the Rinnegan's arsenal. They are the additional Rinne Sharingan abilities that isn't part of the Rinnegan abilities.

When Sasuke first awakened his Rinnegan, it was red in the official coloured manga. This isn't a mistake by the colourer, as Sasuke very conveniently did not show any Six Paths techniques. It is only until after the fight against Kaguya, Sasuke first used the Deva Path technique Chibaku Tensei. By then his eye mysteriously became purple.

A big misconception is that Sasuke's Amenojikara is a unique Rinnegan ability like Madara's Limbo Hengoku. This is incorrect. It is a Rinne Sharingan ability similar to Amenominaka. The same goes for Sasuke's portal creation, which is a Rinne Sharingan ability similar to Yomotsu Hirasaka. Sasuke's Rinnegan seems to possess the watered-down versions of Kaguya's abilities due to being a Kekkei Genkai rather than Kekkei Mora.

Due to having awakened only one Rinnegan, neither Sasuke nor Kaguya have unique Rinnegan abilities.

Momoshiki's Rinnegan was initially red as well and had no showings of any Six Paths techniques. However due to having awakened two Rinnegan, he was capable of the unique ability. With one of his Rinnegan, he was able to greatly absorb jutsu, and with the other, he can accelerate the process by converting it into a Chakra Fruit first. This is similar to Madara's unique ability Limbo. Due to already having awakened both Rinnegan, Madara could use Limbo even if he possess one Rinnegan only. However, with the second Rinnegan, it greatly enhances his unique ability by producing 4 Limbo clones.

However after he absorbed Kinshiki, his Rinnegan became yellow (purple in the movie), and coincidentally he was able to use Deva Path now.

This suggests that Kinshiki has a Rinnegan that is capable of at least two of the six paths techniques, namely Deva Path and Preta Path, the same ones that Sasuke has shown so far. Deva Path was shown by Momoshiki. In the Boruto databook, Kinshiki was said to possess the ability of any Ninjutsu, in which the same description was given to Preta Path in the Fourth Databook. Kinshiki was also shown to be able to create trans-dimensional portal both visually and functionally similar to that of Sasuke.

Another misconception is that Outer Path and Limbo can only be used by an authentic Rinnegan, therefore Edo Tensei reanimations were unable to use it. The truth is that there is no real difference between the artificial Rinnegan and the authentic Rinnegan. Edo Tensei reanimations and Six Paths of Pain were unable to use Outer Path because it can only be used by the living, therefore Nagato himself as well as Revived Madara was able to use it. Limbo was only able to be used by one who has possessed both Rinnegan, therefore Juubito wouldn't be able to use it despite having Six Paths Chakra. Living Nagato, despite having both Rinnegan, does not have Six Paths Chakra unlike Revived Madara, hence unable to use Limbo as well.

The Rinnegan is like the reverse of Mangekyo Sharingan. While the Rinnegan gives the shared ability in each eye and unique ability with both, the Mangekyo Sharingan gives an unique ability in each eye and a shared ability (Susanoo) with both.'

Another thing is that the same technique can vary between different Rinnegan. At least in the main series, we have only seen two Rinnegan, that of Madara and that of Sasuke, and the abilities that they both show are different in some way.

Chibaku Tensei created using Madara's Rinnegan (that includes Pain) is by creating a black sphere where everything gravitates towards it, while that created by Sasuke's Rinnegan is able to pinpoint the target itself similar to Six Paths Chibaku Tensei, except without the need of physical contact.

Tomoe

The number of Tomoe on the Rinne Sharingan is an indication of how much chakra the user has, and this is pretty consistent throughout the series. Madara dropped from 9 Tomoe to 6 Tomoe after he used Infinite Tsukuyomi, and the same happened to Kaguya when she repeatedly used Amenominaka, an ability that drains chakra very quickly according to Black Zetsu. However, she regained 12 Tomoe after absorbing more chakra from the victims of Infinite Tsukuyomi in her root time space.

One misconception is that Hagoromo has the Rinne Sharingan that he entrusted to Sasuke. However, Hagoromo does not need to possess the same power as what Sasuke has awakened, because that is the result of Sasuke's eye reacting with the Six Paths Chakra given by Hagoromo. There is also no other evidence that shows Hagoromo having the Rinne Sharingan other than this scan on Creation of All Things. However, the Rinne Sharingan was shown behind Hagoromo, with Hagoromo's both eyes visibly lack of Tomoe. The Rinne Sharingan also look more like a physical structure, with the Yin Yang symbol at its center, rather than a biological body part.

However, there is still some possibility that Hagoromo might have the Rinne Sharingan, despite never showing it on panel. It might just be Hagoromo's chakra-deficient state, causing him to lose his Tomoe the same way Sasuke does when he is low on chakra.

The most Tomoe is actually seen from the original Ten Tails, the progenitor of chakra itself. It was seen with at least 4 rows of Tomoe.

In Boruto, Sasuke's Rinne Sharingan drops from 6 Tomoe directly to 0 Tomoe when he was low in Chakra, essentially reducing it to just being a normal Rinnegan.

However, before he master the Rinnegan in Shippuden, he was unable to have this level of control, and his Rinnegan was immediately rendered useless when he was low on chakra.

The third Rinnegan on Momoshiki's forehead awakened from eating the fruit of Kinshiki might belong to Kinshiki, just like how Kaguya awakened the Rinne Sharingan of the God Tree after eating its Chakra Fruit. Kinshiki's Rinnegan is likely hidden behind his forehead cover similar to Madara's third eye.

Kinshiki has also shown to be able to travel across dimensions with a technique visually similar to Kamui, likely a Kekkei Genkai than Kekkei Mora unlike Yomotsu Hirasaka.

This suggest that Kinshiki's Dojutsu, and hence Momoshiki's third eye, is a Rinne Sharingan. This is a similar case to Kaguya as he, too, awakened it on his forehead by eating the fruit of God Tree.

The reason why Momoshiki's third eye has no Tomoe might be due to the lack of chakra when the Tomoe disappears, just like Sasuke's Rinnegan.

In the Boruto anime, Urashiki has a 6-Tomoe Kekkei Mora Rinne Sharingan as his left eye. It has shown capable of Yomotsu Hirasaka, but probably not enough chakra to cast something like an Infinite Tsukuyomi or Amenominaka.

Urashiki is also the only character who have shown to be able to deactivate his Rinnegan when not in use. (not counting Sasuke from The Last) He is also the only character with two Dojutsu on the same eye, Byakugan and the Rinne Sharingan. It is not a Byaku Rinne Sharingan as his Byakugan veins disappear when the Rinne Sharingan is activated.

While we can count the rings of Tomoe for a Rinne Sharingan, the same way doesn't apply on a regular Rinnegan without any Tomoe regardless of chakra levels. However in the anime, the innermost ring of the Rinnegan usually has a darker shade of purple, which might be a way for the series to show the chakra levels depending on how many different shades of colour the Rinnegan has. Unfortunately, this concept was never properly utilised in the end product.