Chicago's Monolith have been at the intersection of progressive and thrash metal since 1993, one of the longer-tenured acts in the city's underground, built on technical riffing and ambitious song structures.

Snoqualmie, Washington's Monster Blood are a hyperactive collision of crossover thrash, grindcore, power metal, and powerviolence — a chaotic, tongue-in-cheek band that refuses to settle into any single lane since forming in 2015.

A goregrind act out of Los Angeles, Monster Creamer formed in 2025 and lean into the deliberately absurd, grotesque end of grindcore, delivering blastbeat-heavy noise with all the restraint the genre demands — which is none.

Moon Drunk is a Chicago trio formed in 2021 colliding grindcore velocity with black and death metal extremity into compact, caustic bursts of noise. Operating out of the city's underground, they favor speed and ferocity over nuance — short, punishing songs with no room for comfort.

Moon Witch is a Dayton, Ohio band formed in 2021 that tears through black metal, death metal, and grindcore in roughly equal measure, trading in speed and ugliness with clear enthusiasm. Their Bandcamp handle — moonwitchusbm — signals a commitment to underground black metal aesthetics even as the grind influence pulls them toward pure noise.

New Bedford, Massachusetts's Moral Decay blend death metal's gravity with grindcore's blunt-force speed and brevity, a combination that's been a fixture of the New England underground since their 2013 formation.

Denver's Moral Deceit combine death metal's crushing brutality with grindcore's breakneck brevity, operating in the Mile High City's underground since 2013 with a blunt, pulverizing approach to extreme music.

Merrick, New York's Morbid Curiosity began with death metal and grindcore before expanding into alternative metal and hardcore territory — a restless band formed in 2020 that resists settling into any single extreme subgenre.

South Carolina death metal and grindcore project that surfaced in 2025, blending the gut-punch brevity of grind with the relentless brutality of death metal. An extremely new entry into the underground, their Bandcamp presence signals a raw and confrontational approach.