Which descriptor could be used for an atmosphere that conjures feelings of dread?

The term "Stygian" is derived from the River Styx in Greek mythology, which is often associated with the underworld and represents darkness, obscurity, and a foreboding atmosphere. When describing an atmosphere as Stygian, it conveys a sense of overwhelming darkness and dread, painting a vivid picture of a place that is not only gloomy but also evokes feelings of fear and unease. This aligns perfectly with the prompt's request for a descriptor that conjures feelings of dread.

In contrast, "Stentorian" refers to a loud and powerful voice, which does not relate to atmosphere or feelings of dread. "Striated" typically describes something marked with linear grooves or stripes, and is often used in a geological or biological context rather than an emotional or atmospheric one. "Runic" relates to ancient writing systems, especially those associated with Norse or Celtic cultures, and while it may suggest mystery, it doesn't inherently evoke feelings of dread in the same way that "Stygian" does.