It’s very likely that the first-ever Mayhem Fest is the concert of the summer for SA’s rockers, featuring multi-platinum rock acts Slipknot (right) and Disturbed in a co-headlining slot. The much-buzzed-about road show features hard music’s most influential bands and a new wave of heavy-hitting acts in an amp-shattering festival showdown that includes underground guitar heroes Dragonforce, the surreal, progressive, and unrepentantly heavy style of Mastodon, and Machine Head’s unique brand of bludgeoning metal. The Knot’s been off the radar for a few years with various members pursuing other musical projects, but they’re back heavier than ever and are set to release their fourth album, All Hope is Gone, in late August. $33-59, 1pm, Verizon Amphitheater, 16765 Lookout Rd.,
(210) 224-9600.