The Inseingan (インセイン; The Insane's Eye) is a extremely unstable dojutsu used by Sasuke Uchiha and Nekone Uchiha.
The Inseingan was created by Nekone Uchiha during the 1st Ninja World War. After so many defeats, he became extremely enraged, his chakra began to change, and his Sharingan became ultimately unstable. The color changed from red to green, and the three temoes shape into an unknown fashion.
The Inseingan has atleast 5 or more techniques that are extremely dangerous. The Hasonshin (Corruption God) is a technique that corrupts time immediately to the user's choice. It is weaker than Tsusuyomi, but the speed is greatly intensified. The user however risks a extreme amount of chakra, more than Tsusuyomi. Chūwashin (Neutralization God) stuns the opponent for a period of time, but requires extreme chakra use, however, less than Hasonshin. Atomikku (Atomic God) is a technique that releases deadly bolts of radiated lightning, but yet requires a fatal amount of chakra, and usually, if not the Kōkyūtekina Inseingan, the eye immediately blinds.