Swans are the heaviest band in the world. Michael Gira’s experimental rock troupe barely dip into ‘metal’, but their final London show with this post-reformation line-up is more brutal than any Cannibal Corpse gig. Delivering more than two hours of sphincter-tightening intensity, the only criticism of tonight’s sonic punishment is it’s basically identical to last year’s setlist. But Swans aren’t a jukebox. Michael embodies the power and vulnerability of the band, crumpling into his guitar, wincing at feedback, cajoling his band into barrages of white noise on as-yet-unreleased tracks. But they’re not just racket-makers; they’ve always relied on rhythm and bass-heavy groove, and nowhere is this more apparent than on Screen Shot, the opening riff ringing out again and again as Christoph Hahn fiddles with his malfunctioning lap steel guitar. And that’s fine. This is experimental rock – it isn’t slave to convention. Tonight it’s borderline religious, Michael flailing his arms, eyes closed and yabbering esoteric hymns to rapturous applause. Swans’ next iteration will be just as vital. They won’t die again.