Jucifer are a two piece American sludge metal band signed to Relapse Records. The band's members are Gazelle Amber Valentine on lead guitar and vocals, and her husband Edgar Livengood on drums. They travel in an RV and are "nomadic in nature", preferring to tour constantly, living in their tour vehicle, rather than following the normal practice of album release/tour/time at home. Jucifer is notable for the extreme volume at which they perform, and the gigantic wall of amplification used for Valentine's guitar, as well as the dichotomy that has existed between much of the recorded material and their live shows.

The husband-and-wife duo starred in a film by Derek Cianfrance titled Metalhead, a drama centering on a drummer suffering from hearing loss and learning the meaning of silence. Livengood and Valentine play as themselves in the film. The film has been in production since 2009 but no release date has been announced.