Rigor Sardonicous started their activity in 1988 and that fact probably make them the oldest continually active US doom metal band. This band is notable for combining extreme doom metal with deathgrind. They are arguably one of the first bands in metal to use extremely deep gurgling vocals that are now common in goregrind. In other words, the music is a combination of thick, super downtuned guitars, ultra deep vocals, crushing industrial cymbals and absolutely unique, bleak and hopeless atmosphere.