Probot was a heavy metal side project of ex-Nirvana drummer and Foo Fighters lead guitarist and lead-singer Dave Grohl. Described by Grohl as "a death metal Supernatural", the album mixes instrumentals recorded by Grohl himself with various metal singers which the musician idolized. The album was released in February 2004 by Southern Lord Records. It featured one single entitled "Centuries of Sin"/"The Emerald Law".