Hideous Mangleus is a grindcore band from Pittsburgh, Pennsylvania, formed in March 1989. Emerging from a background in hardcore and punk, they developed an early sound that blended grindcore, death metal, and punk, contributing to the growing “deathgrind” style in the U.S. underground.

The band gained attention in tape-trading circles with their 1990 demo All Your Friends Are Dead, followed by the We Live... ...You Sleep and Unearthing Grandma’s Grave EPs.
These releases established their lo-fi production, fast-paced songwriting, and a mix of horror themes and dark humor.

In 1996, Hideous Mangleus released their full-length album All Your Friends Are Dead, a 29-track recording that reflected the band’s chaotic style and underground roots.
Over time, the album became a cult favorite within grindcore circles.

The band’s material has been revisited and reissued by labels such as Hells Headbangers, helping introduce their recordings to a wider audience and preserving their place in the history of grindcore.