Mortiferum’s music exists in near-total darkness. The Olympia death/doom quartet builds labyrinths out of suffocating atmosphere, pounding drums, and churning squalls of detuned guitar. Only when your eyes adjust can you see an occasional sunbeam penetrating the gloom—a snaking, melodic lead or a clatter of cymbals that interrupts the slow march and sends the band into a headlong hurtle.