Roots of Dethklok

High on Fire is an American heavy metal band from Oakland, California, that was formed in 1998. Matt Pike, the band's frontman and founder, also played guitar for Sleep. High on Fire won the 2019 Grammy Award for Best Metal Performance with their song "Electric Messiah". The band has released nine studio albums, with their newest, Cometh the Storm, released in 2024.

Castle Rat is an American doom metal band formed in Brooklyn, New York, in 2019. Known for their "medieval fantasy doom metal" aesthetic, they blend traditional doom and heavy metal with theatrical live performances inspired by Black Sabbath and Frank Frazetta's fantasy artwork. Led by vocalist and rhythm guitarist Riley Pinkerton, the band gained recognition for their debut album Into the Realm (2024) and elaborate stage shows featuring their nemesis, "The Rat Reaperess".

Converge is an American metalcore band formed by vocalist and artist Jacob Bannon and guitarist and producer Kurt Ballou in Salem, Massachusetts, in 1990. While recording their landmark fourth album Jane Doe in 2001, the group became a four-piece with the departure of guitarist Aaron Dalbec and the addition of bassist Nate Newton and drummer Ben Koller. This lineup has remained intact since. The members have also been involved in various side-projects and collaborations, including the bands Supermachiner (Bannon), Old Man Gloom (Newton), and Mutoid Man (Koller). With their extremely aggressive and boundary-pushing sound, rooted in hardcore and heavy metal, they are pioneers of metalcore and its subgenre mathcore.