A previously unreleased Black Sabbath song has found its way online. The track, called “Slapback,” features Ronnie James Dio on vocals. The newly released “Slapback” was found in a rehearsal recording the band did in 1979. You can find “Slapback” on a Youtube channel run by the estate of longtime Black Sabbath keyboardist Geoff Nicholls. Have you listened to this unreleased song? What do you think of it? What do you think of Dio’s work with Black Sabbath?