The increase of musicianship on "Ride the Lightning" caught the attention of major record labels. Metallica was signed to Elektra Records, and began working on its third album, "Master of Puppets", which is considered by most critics to be a landmark album in heavy metal. Among the tracks featured in the album are the instrumental "Orion" (which features a prominent lead bass section) and the title track, which was Burton's favorite Metallica song. "Master of Puppets" is the band's commercial breakthrough release, and Burton's final album with Metallica.