Erra belong to a clutch of bands who pioneered the unique sonic dualities that define progressive metalcore. With early cuts like “White Noise”, the band helped establish the genre's trademark tension between pristine fret-work and cruel start-stop riffs, while tracks like 2013's “Alpha Seed” laid the groundwork for the style's tug-of-war between melodic vocals and primal grunts. As Erra have evolved, so has their ability to bake contrasts into their songs; the symphonic “Luminesce” pits ghostly atmospherics against breakdowns so technical, they should come with schematics.