Arturo Díaz Mendoza (March 23, 1952 – August 21, 2018) was a Mexican professional wrestler who performed under the ring name Villano III (in Spanish Villano Tercero). Díaz was a second-generation wrestler, son of luchador Ray Mendoza and the father of professional wrestlers Villano III Jr. and El Hijo del Villano III himself. All five of the Díaz brothers used the Villano name; José de Jesús (Villano I), José Alfredo (Villano II), Tomas (Villano IV) and Raymundo (Villano V). Of the five Villanos, Arturo was considered the most successful in terms of championship and Lucha de Apuesta (bet match) wins as well as the most talented luchador in the family. He retired from wrestling in 2015 due to health issues stemming from wrestling. A few days after his death, he was inducted in the AAA Hall of Fame.
During his 35 year career, Arturo Díaz was one of the featured performers for the Universal Wrestling Association, and for all the all major Mexican wrestling promotions such as Consejo Mundial de Lucha Libre and AAA as well as numerous notable smaller Mexican promotions like International Wrestling Revolution Group. Díaz was an enmascarado, or masked wrestler, up until 2000 where he lost to Atlantis and had to unmask as a result. The match against Atlantis was later voted "Match of the Year" in the Wrestling Observer Newsletter year-end awards. In contrast one of his last matches ever, at Triplemanía XXIII was voted the "worst match of the year" in 2015.