Ozzy Osbourne will reunite with all of the original members of Black Sabbath for the first time in 20 years, in a gig that will be his last and that's being billed as the “greatest” heavy metal show ever,

The original line-up of heavy metal legends Black Sabbath, including Ozzy Osbourne, will play together for the first time in 20 years at a one-off concert on July 5 in Birmingham, England, organisers said on Wednesday.

Scheduled for July 5 at Villa Park, the show will feature Osbourne playing a short solo set, followed by him joining Sabbath for what's described as his "final bow." There will also be performances by Metallica, Slayer, Pantera, Gojira, Halestorm, Alice in Chains, Lamb of God, Anthrax and Mastodon.