Gurengan

Akametame (赤目為, Red Eye Effect) is the name coined to the rare dojutsu ability previously only known as "Ranmaru's Kekkei Genkai." When activated, the eyes glow red in color (hence its name) and grant the wielder a multitude of abilities such as: penetrating vision, disruption of other dōjutsu, and unique healing through life-force energy manipulation.