In October 2005, to celebrate its 25th birthday, legendary U.S. metal label Roadrunner Records threw an ambitious two-part family reunion. First, an album, Roadrunner United, featuring music written by four of the most talented and game-changing alumni from its stable acting as ‘team captains’ (Machine Head’s Robb Flynn, Slipknot’s Joey Jordison, Fear Factory’s Dino Cazares and a then-19-year-old, prodigiously gifted Matt Heafy from Trivium), and performed with an army of other faces from the label’s quarter-century of noise. It was followed by a gig at New York’s Nokia Theatre that December, at which even more artists joined in. Specifically, 39 players from 25 different bands did a turn, from Machine Head and Sepultura, to death metal OGs Obituary and Deicid...