The fourth and final season of the animated show Metalocalypse originally aired on Adult Swim from April 29 to July 15, 2012 with 12 episodes. The show follows virtual death metal band Dethklok. This season returned to the original 11-minute-long episode format. Several songs from this season were included in the album Dethalbum III, which was also released in 2012. The season four DVD/Blu-ray was released on October 30, 2012 through Adult Swim/Warner Home Video.

Metalocalypse is an American musical adult animated television series created by Brendon Small and Tommy Blacha for Adult Swim. It premiered on August 6, 2006. The television program centers on the larger-than-life melodic death metal band Dethklok, and often portrays dark and macabre content, including such subjects as violence, death, and the drawbacks of fame, with hyperbolic black comedy. The show was widely heralded as both a parody and a pastiche of heavy metal culture.