Metallica were joined by onstage by Black Sabbath's Ozzy Osbourne and Geezer Butler Saturday night at the Fillmore Theater in San Francisco during the final of four special gigs there to celebrate the band's 30th anniversary. Former Metallica member/current Megadeth frontman Dave Mustaine was also a special guest during the show, along with other former members Jason Newstead, Lloyd Grant, Ron McGovney and Hugh Tanner.

Metallica again performed a career-spanning 20-song set, although on this night it was heavy with selections from 1983's 'Kill 'Em All.' For the fourth time in four shows, they also premiered a 'Death Magnetic' outtake, this time busting out a tune titled 'Rebel Of Babylon.' A rough-mix recording of 'Babylon' was sent to Metallica fan club members and can be streamed here.

One half of James Hetfield's special guest wish list came true when Ozzy showed up, and the Prince of Darkness and Geezer joined Metallica for a few songs, including the Sabbath classics 'Iron Man,' 'Paranoid' and 'Sabbra Cadabra.'

But the biggest moment of the night was the return of Mustaine, who was so excited to be in town for the show he tweeted about it beforehand. After a period of serious bad blood between Mustaine and his former bandmates, the Megadeth star sat in for five songs, including 'Hit The Lights,' 'Metal Militia,' 'Phantom Lord,' 'Jump In the Fire' and 'Seek And Destroy.'

Watch Fan-Shot Footage of Metallica with Ozzy and Geezer: