History and Abilities of the Sharingan

Introduction

• Sharingan is a Dojutsu Kekkei Genkai of the Uchiha clan in Naruto.
• One of the three great Dojutsu, alongside Byakugan and Rinnegan.
• Originated from Kage Otsutsuki's Rinnei Sharingan.
• First manifested as an independent form by Indra Otsutsuki.

Acquisition of Sharingan

• Triggered by powerful emotional conditions related to a precious person.
• Brain releases special chakra affecting optic nerves, transforming eyes.
• Initial awakening may cause timing issues due to enhanced perception.
• Usually starts with one Tomoe, can develop to three Tomoe through emotional growth.

Sharingan's Abilities

Eye of Insight

• Enables user to see chakra, distinguish composition and source.
• Provides clarity of perception: read lips, mimic movements, see on cellular level.
• Anticipate opponent's moves based on muscle tension.
• Copy jutsu with near-perfect accuracy, except for Kekkei Genkai or unlearned nature transformations.

Eye of Hypnotism

• Perform Genjutsu Sharingan through eye contact.
• Suggest thoughts/actions, control body, and manipulate tailed beasts.
• Mimic opponent movements and suggest actions, potentially seeing the future.

Special Techniques

• Izanagi: Warp reality, escape death, causes blindness in the performing eye.
• Izanami: Infinite loop, created to reprimand Izanagi abusers.

Transformations

Mangekyou Sharingan

• Evolved through trauma of loss, grants user-specific jutsu.
• Causes blindness over time; eternal Mangekyou achieved by sibling eye transplant.

Rinnegan

• Evolved from Sharingan with mixed Asura's and Indra's chakra.
• Restores eyesight, fixing blindness from Izanagi use.

Notable Users and Variations

Itachi Uchiha

• Awakened Mangekyou after best friend's suicide.
• Techniques: Tsukiyomi and Amaterasu.

Sasuke Uchiha

• Awakened after Itachi's death.
• Able to use Amaterasu and Susanoo.

Madara Uchiha

• First Uchiha to awaken Mangekyou.
• Achieved eternal Mangekyou, eyes evolved to Rinnegan.

Obito Uchiha

• Awakened after Rin Nohara's death.
• Techniques: Kamui, teleportation abilities.

Shisui Uchiha

• Awakened with friend's death.
• Technique: Kotoamatsukami, mind control.

Others

• Indra Otsutsuki, Shin Uchiha, Fugaku Uchiha, and Hagoromo Otsutsuki with unique abilities and awakenings.