Kurakugan

The Kurakugan (暗く目, Kurakugan) is the dōjutsu kekkei genkai of the Kodachi clan, appearing selectively among its members and their descendants. The Kurakugan is recognized by its glassy-blue pupil and black sclera, being characterized as "eyes of the underworld".

Abilities
The Kurakugan, grants the user a cloak of malleable yin-chakra that can be used for a wide variety of purposes from offensive attacks, defensive shields and even precise surgery techniques. The user is also able to place people under a genjutsu through eye contact.

Trivia

 * During the time of the Land of Ash, possessing the Kurakugan granted its owner special privileges, even if they were not part of the ruling Kodachi clan.