When a wielder of this Kekkei Genkai experiences a powerful emotional condition with regards to a person precious to them, their brain releases a Special Form of Chakra that affects the optic nerves, transforming the eyes into Sharingan.

The Rinnegan is reputed as the most exalted eye amongst the Three Great Dōjutsu.
It's said that in times of disorder, one who wields the Rinnegan is sent down from the heavens to become either a God of Creation who will calm the world or a God of Destruction who will reduce everything to nothingness.

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