Assfactor 4 was a hardcore punk band from Columbia, South Carolina formed by two members of Tonka (Jay and Alex) and two members of Unherd (Eric and Kevin). They formed in the fall of 1992 and broke up in late 1997. Assfactor 4's sonic approach drew heavily from San Diego's early-1990s group Heroin, but their song structure was notably more akin to 1980's thrash and hardcore, placing Assfactor 4 in a unique position within the DIY hardcore scene of the era.