Prior to forming the heavy metal band Dio in 1982, singer-songwriter Ronnie James Dio had fronted three major bands: Elf, Rainbow, and Black Sabbath. ∙ Dio’s Platinum debut, 1983’s Holy Diver, is a genre-defining heavy metal album that spawned two classic hits, “Holy Diver” and “Rainbow In the Dark.” ∙ Their lineup has included Def Leppard guitarist Vivian Campbell, Quiet Riot bassist Rudy Sarzo, and AC/DC drummer Simon Wright. ∙ Ronnie and bandmates Jimmy Bain and Vivian Campbell cowrote “Stars,” a single recorded by the all-star heavy metal project Hear ’n Aid to raise money for African famine relief. ∙ In 1999, the South Park episode “Hooked on Monkey Fonics” featured an animated version of Dio performing “Holy Diver” at a school dance. ∙ A frequent collaborator with Tenacious D, Ronnie was featured in the 2006 movie Tenacious D in The Pick of Destiny, and duo appeared in Dio’s video for “Push.” ∙ While it continues to be a matter of some debate, Ronnie James Dio takes credit for popularizing heavy metal’s iconic “devil horns” hand gesture.