A sludge, doom, and post-metal act from the southern Hungarian university city of Szeged, Boru has been crafting heavy, atmospheric compositions since 2018. The band merges the crushing weight of sludge with the expansive dynamics of post-metal.

Mastroyany is a death metal (early); hardcore/thrash metal (later) band from Ryžoviště, Czech Republic, formed in 2019. They forge aggressive extreme metal at the crossroads of death and thrash.

Masugn is a death/thrash/black metal band from Gothenburg, Sweden, formed in 2015. They forge extreme metal at the fierce intersection of black and death metal.

A thrash/death metal band from the Madrid suburb of Torrejón de Ardoz, Matadero — Spanish for 'slaughterhouse' — delivers exactly the kind of visceral aggression the name promises. Formed in 2016, they combine Bay Area thrash velocity with death metal heaviness.

Mathrus is a experimental death/thrash/black metal band from Ryazan, Russia, formed in 2021. They forge extreme metal at the fierce intersection of black and death metal.

Matraque is a sludge, death, and doom metal band from Minsk, Belarus, formed in 2013 that grinds through low-tuned, punishing heaviness. Their approach layers crushing sludge grooves with death-doom weight, carving out a suffocating sonic space within the Belarusian underground.

A melodic death metal act from Warsaw, Matternysh has been delivering harmonized aggression since 2016. The band brings Scandinavian-influenced melodeath to the Polish capital.

Maudit is a death/black metal band from France, formed in 2014. They forge extreme metal at the fierce intersection of black and death metal.

A death metal act from Lille in northern France, Maufé emerged in 2023 with a sound that draws from the old-school death metal tradition. The band contributes to the growing extreme metal scene in France's northern industrial heartland.