Master of Reality is the third album by heavy metal band Black Sabbath, released in 1971 (see 1971 in music). On this album, guitarist Tony Iommi began de-tuning his guitar down three semi-tones (or one and a half steps, or C♯) to reduce tension in the strings, making it easier to play with his injured fingers. This led to a lower, sludgier sound that became the Master of Reality trademark. The lyrical themes include: drugs, solitude, war and theology. "After Forever" is credited lyrically to Iommi (the only Sabbath lyrics solely credited to him thus far) and is heavily Christian-themed. On original US pressings of the album, several songs had subtitles given to segments, making it appear that there were more songs on the album than there actually were: the coda of "Children of the Grave" was given the title "The Haunting," the intro to "Lord of This World" was titled "Step Up," and the intro to "Into the Void" called "Deathmask." (Subtitles were also provided to several songs on the US releases of the first two Black Sabbath albums.) Also, the album's title was incorrectly listed as "Masters of Reality" on the labels of original Warner Bros. (green-label) US pressings. Subsequent pressings corrected the album's title on the label, and removed the three subtitles. This album is cited as an influence by many Stoner Metal and Sludge Metal artists. In the UK the album reached #5. Initial pressings came in an embossed 'envelope sleeve', which contained a poster of the band and the generic Vertigo inner bag, although for this album the 'swirl' was white-on-black, rather than black-on-white. This was the first Black Sabbath sleeve on which the lyrics were reproduced, being on the rear of the sleeve. On the Billboard Pop Albums chart, Master of Reality peaked at #8. In 2003, the album was ranked number 298 on Rolling Stone magazine's list of the 500 greatest albums of all time.. It was the third and final Black Sabbath album to be produced by Rodger Bain. Many of the songs would be played on the The Reunion Tour (more than on the tour contemporary to the album).