Well, this promises to be an orgy of unconventional headbanging. As internationally feted rockers Boris and hardcore/post-rock vets Envy reconvene for their third show under the 'Leave Them All Behind' banner, they're scaling things up into a two-day event featuring some overseas guests alongside the local acts. You couldn't ask for a more mind-melting pair of headliners than Sunn 0))) – they of the dry ice, super-slow riffs and absolutely bonkers stage specs – and Godflesh, the recently reunited industrial metallers led by Kevin Martin cohort Justin Broadrick. The Sunn 0))) day looks to be the sludgier of the two, as Boris reprise their epically sprawling third album Flood, with support from doomy singer-songwriter Chelsea Wolfe and Ai Aso. Godflesh's bill takes things in a more uptempo direction, with abrasive support from Envy, black metal shoegazers Deafheaven and Kansai grindcore act Mortalized.