Opetherion has 2 Slipknot concerts.

Formed in 1995, Slipknot emerged from Des Moines, Iowa as leader of the burgeoning alternative and nu metal movement alongside bands like Korn, Mushroomhead, and System of a Down. As part of the band's horrorcore aesthetic, each member wears a unique mask and matching uniform, often a jumpsuit. Shows make extensive use of pyrotechnics, explosions, extravagant lighting, computer screens, and crazy antics that often involve members of the audience. In 2012, Slipknot created its own music festival called Knotfest. The first Knotfests took place in Council Bluffs, Iowa and Somerset, Wisconsin. It 2014, Knotfest became an international event when Slipknot hosted the event in Chiba, Japan. Since then, Knotfest has taken place in many other global locations, including Colombia, Mexico, Germany, France, Finland, Argentina, Chile, Brazil, and Australia. Slipknot has headlined every Knotfest since its inception.