By 2007, the original Black Sabbath were in limbo. Iommi and Butler decided to move things forward with Ronnie James Dio, recording three new songs for a greatest hits compilation of Dio-era Sabbath material.

The tracks proved two things: Iommi was still an unsurpassable riff writer, capable of crushing any young metal pups with his heaviness. Secondly, a reunion with Dio now made perfect sense. Except it wouldn't be Sabbath - to avoid confusion with the Ozzy-fronted incarnation of the band, the reunion with Dio would be named after their first album together: Heaven And Hell. Though it would be without Bill Ward, who declined to take part, so Vinny Appice returned to the drum stool.

"With Ronnie we scrutinise the music a lot more," Iommi told Guitarist magazine in 2009, "Because Ronnie has a lot of ideas. I'll come up with initial riff then he might suggest changing it a little and going to this bit. We pull the music apart more. It's good because he might hear something different to me - then I can say, Oh that's good or it's not. It works."

With the resulting international Heaven & Hell tours going down a storm, an album followed. 2009's doomy Devil You Know was a victory, the finest 'Sabbath' album since Dehumanizer with its centrepiece Bible Black proving that qualifying for a bus pass hasn't diminished the heaviness of a re-inspired Sabbath one iota.