Psyopus, a mathcore band from Rochester, USA, was formed in 2002. The group originated from Christopher Arp's one-man project "Stranglefuck," which released a demo featuring instrumental versions of songs later included on Ideas Of Reference (2004). Psyopus officially began with Arp on guitar, Fred DeCoste on bass, Greg Herman on drums, and Adam Frappolli as vocalist. Their first release was the EP 3003 in 2003, followed by their debut album Ideas of Reference in March 2004 under Metal Blade Records. The band's complex compositions and technical proficiency garnered both praise and criticism. After a US tour, Herman left due to personal reasons, leading to several drummer changes. In 2007, Psyopus released Our Puzzling Encounters Considered, featuring more intricate arrangements and the instrumental track "Siobhan's Song". The band continued with various lineup changes, including multiple vocalists. Their third album, Odd Senses, was released in 2009.