Sharingan

The Sharingan (写輪眼) is a legendary doujutsu (eye technique) in the Naruto world, originating from the Uchiha clan. The Sharingan allows its user to see chakra, copy jutsu, and cast various genjutsu effects. The Sharingan can also evolve into the Mangekyou Sharingan and Eternal Mangekyou Sharingan, each with greater power and unique side effects.