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The opening years of the 1980s saw a number of changes in personnel and direction of established hard rock acts, including the deaths of Bon Scott, the lead singer of AC/DC, and John Bonham, drummer with Led Zeppelin. Whereas Zeppelin broke up almost immediately afterwards, AC/DC pressed on, recording the album Back in Black (1980) with their new lead singer, Brian Johnson. It became the fifth-highest-selling album of all time in the US and the second-highest-selling album in the world. Black Sabbath had split with original singer Ozzy Osbourne in 1979 and replaced him with Ronnie James Dio, formerly of Rainbow, giving the band a new sound and a period of creativity and popularity beginning with Heaven and Hell (1980). Osbourne embarked on a solo career with Blizzard of Ozz (1980), featuring American guitarist Randy Rhoads. Some bands, such as Queen, moved away from their hard rock roots and more towards pop rock, while others, including Rush with Moving Pictures (1981), began to return to a hard rock sound. The creation of thrash metal, which mixed heavy metal with elements of hardcore punk from about 1982, particularly by Metallica, Anthrax, Megadeth and Slayer, helped to create extreme metal and further remove the style from hard rock, although a number of these bands or their members would continue to record some songs closer to a hard rock sound. Kiss moved away from their hard rock roots toward pop metal: firstly removing their makeup in 1983 for their Lick It Up album, and then adopting the visual and sound of glam metal for their 1984 release, Animalize, both of which marked a return to commercial success. Pat Benatar was one of the first women to achieve commercial success in hard rock, with three successive Top 5 albums between 1980 and 1982.

What singer replaced Ozzy Osbourne in Black Sabbath?
Ronnie James Dio