If your debut album is hailed as the future of an entire genre before you have even left your teens, there is always a risk of freezing in place. Of repeating yourself. But ever since the furious collision of post-punk and hardcore on 2011’s landmark debut “New Brigade”, Iceage have refused to become prisoners of their own mythology. With every album, the Copenhagen band has kept moving, expanding their sound from raw punk urgency into something increasingly melodic, romantic and impossible to pin down. On this year’s acclaimed “For Love of Grace & the Hereafter”, they arrive at perhaps their richest incarnation yet. Punk immediacy meets pastoral beauty, rock’n’roll swagger, country flourishes and towering melodies, while Elias Rønnenfelt’s songs have become less concerned with confrontation than with the strange ways love, devotion and obsession reshape the people caught inside them. Nearly two decades into their career, Iceage remain one of rock’s most restlessly inventive bands. This summer, they bring that edgy spirit to Stay Out West.