San Diego progressive metal outfit formed in 2022, blending metal's technical weight with hard rock's melodic sensibility into an accessible yet complex sound. Slavior occupy a crossover space where progressive structure meets arena-ready hooks.

San Francisco progressive doom metal band formed in 2023, crafting elaborate, slowly unfolding compositions that wed psychedelic atmosphere with heavy, deliberate riffing.

Solus are a Los Angeles post-black metal project active since 2007, weaving atmospheric and introspective textures into a black metal foundation in the manner characteristic of the city's eclectic extreme metal underground.

Sombra are an Anaheim, California progressive/technical death metal band formed in 2019, pursuing a complex and intricate approach to extreme metal that emphasizes compositional sophistication alongside raw brutality.

Sombre Holiday are a Riverbank, California progressive metal band with roots going back to 1994, building a catalog of technically ambitious and melodically rich heavy music over three decades of activity in the Central Valley underground.

Sorizon are a progressive metal band from Orange County, California, formed in 2009, crafting technically driven, compositionally complex metal in the tradition of the genre's West Coast scene, with an emphasis on dynamic range and instrumental precision.

Spaceboy is a San Francisco band formed in 2017, navigating an eclectic intersection of progressive stoner, doom, and death metal. Their genre-blending approach reflects the Bay Area's history of genre-boundary-pushing heavy music, layering psychedelic texture over heavier structural ambitions.

Los Angeles progressive death metal and deathcore act Sporemacide formed in 2025, combining the technical ambition of progressive metal with the heaviness of death metal and deathcore.

Stentorian is a heavy metal band from Los Angeles, California, formed in 2016. They play traditional heavy metal with an emphasis on powerful vocals and driving riffs, working within the rich and competitive LA metal scene.