On his 2015 EP under the name Oneirogen, Mario Diaz de León crafts tense, bracing soundscapes that juxtapose immersive drones with distorted electronic beats and concentrated bursts of harsh noise and screaming. The EP contains far less of the doom metal influence heard on previous Oneirogen recordings, coming closer to the power electronics genre or later works by Prurient. The album's two highlights, "Collapsing" and "Vessel," consist of measured electronic kick-drum blasts and industrial clanging, along with scorching feedback and shrieked, cathartic lyrics about submitting to pain and destruction. The other three tracks on the EP are much calmer, but closing piece "Emergence" has a dark, creeping cinematic melody, coming to a sudden end right as it seems like terror is about to strike. The EP is a short yet powerful outing that encapsulates de León's prowess at creating electrifying atmospheres, and finds him adding new dimensions to his sound.