As they recently did with North Carolina blackened Americana crew Horseback, Relapse makes its entrée into the frightening world of Chicago sound bleeders Locrian with a set, out August 14, comprising some of the band's most excellent and overlooked material. "Omega Vapors", the shorter of their two contributions to a 2010 split called Dissolvers (paired here with 2011's vinyl-only The Clearing and other "rare and unreleased material"), is pure mesmerizing menace. The instrumental opens with a serialized guitar riff that snakes through itself and a keyboard pattern that murmurs in a patois of spooky bass; by piece’s end, though, the guitar has clinches into a fist of squall, while the keyboard obviates its own melody in favor of a deep, drowning roar that's better intuited than analyzed. Conceptually and musically, Locrian often builds altars in praise of ruin; here, "Omega Vapors" is itself that ruin.