Ten years in business, these Saint Louis-based sludge machines attempt the delicate task of balancing a what-you-see-is-what-you-get approach with the ability to surprise. Their 2011 full-length debut, Bronsonic, is a gnarly, bowel-troweling slab of noise that shows their utter commitment to punishing heaviness, though they do offer a sly wink with song titles such as “Santabbath” and “Mazda of Puppets.” Fister have been fairly prolific in the years since, releasing a steady stream of EPs, demos, and split singles with the likes of Primitive Man, Teeth, and Dopethrone. Following 2015’s IV—which contained a single long, unrelenting track designed to stretch the limits of endurance—the group returned last year with No Spirit Within (Listenable). The album shows that Fister are willing to change things up a bit, with a slight turn toward (dare I say) accessibility. They blast away enough of the black earth crusted on their roaring machinery to reveal some lean hardcore roots—particularly on “Cazador,” which picks up the pace enough that in the context of previous material it sounds downright jaunty.   v