Rap-Metal seeks to fuse the most aggressive elements of hardcore rap and heavy metal, and became an extremely popular variation of alternative metal during the late '90s. With few exceptions, rap-metal is far and away the domain of white musicians coming to the form from the metal side of the equation. Prior to the initial emergence of rap-metal, there had been several successful fusions of rap with hard rock guitar -- Run-D.M.C.'s collaboration with Aerosmith on a remake of the latter's "Walk This Way," the Beastie Boys' Licensed to Ill -- but the true birth of rap-metal was Anthrax's comic 1987 single "I'm the Man," which combined a heavy guitar riff (actually the melody of "Hava Nagila") with full-fledged, surprisingly competent rapping.