Akaigan

Overview
The Akaigan is the Kekkei Genkai of the Sheikah race. It allows every Sheikah to copy the exact movements of another, including jutsu. It also allows them to manipulate the shadows, creating purple fire, lightning, and increasing the strength of their chakra by a hundredfold. When the Akaigan is activated, they have a near infinite amount of chakra.

Powers
The Akaigan allows the Sheikah to create fire and lightning to create shadow infused elements. The Kekkei Genkai also allows them to infuse the power of shadow into almost any jutsu. They can also use it to draw shadowy chakra from even the smallest shadow. It also gives them a few special jutsu: the ninjutsu, the Yami, which allows them to create army of shadow beings. The genjutsu, the Orochi, which makes their opponent face their greatest fears in another world, much like the Tsukuyomi of the Sharingan. And the taijutsu, the Power of the Raven, which gives them a limitless source of strength, much like the Lotus, but unlike the lotus, this does not put strain on the body.

History
Long ago, when the goddess Hylia decided to make the Sheikah her chosen guardians, she gave them this power.