When Rolling Stone began compiling the 100 Greatest Metal Albums of All Time, we noticed one trend very early: Ozzy Osbourne was the genre's MVP. He appears on more records than any other single artist on the list, including five with Black Sabbath and two of his own solo releases. Moreover, he appears on three records in the top 10 – his first solo LP (Blizzard of Ozz, number nine), Black Sabbath's self-titled debut (number five) and Black Sabbath's Paranoid, which topped the entire list.For going on half a century, the singer's stentorian voice has gamely pierced through the monolithic guitar tones of Tony Iommi, Randy Rhoads and Zakk Wylde. He's an indefatigable frontman whose onstage and offstage antics have inspired countless legends. And, even though he hasn't always been the most amenable to being described as a heavy-metal artist ("I hate that terminology," he told Rolling Stone last year, "because it goes from Poison to fucking Black Sabbath and there is quite a fucking difference"), he's been an ardent supporter of the genre. He took Metallica, Motörhead and Mötley Crüe out on their first big tours, and on his frequent Ozzfest festival tours, he's provided stages for Slipknot, Tool, Pantera, Slayer and countless others. Because Osbourne is not only one of metal's progenitors but one of its biggest supporters, Rolling Stone reached out to him early in the process of compiling the Greatest Albums list to find out what his favorites were. He emailed us a list of his 10 favorites along with a few words about why they're cornerstone albums for him and for metal.