Marthiria were a thrash metal band from São Luís, Maranhão, active from 2006 until their split in 2010, with a lineup anchored by vocalist/guitarist Andre Nadler and guitarist Rodrigo Lages. They released the EP Sobrevivendo ao Caos (2008), a direct, riff-driven effort in the tradition of Brazilian thrash that earned them a foothold in the local underground before the band disbanded.

Marthirio is a two-piece thrash/crossover band from Santa Fe, Argentina, formed in April 2018 by Matias Echauri (guitars, bass, and vocals) and drummer Lucas Engler. Their debut album Mosh Till Death, recorded at Superyeah Studios and mixed by Anibal Rodriguez at Blazing Hatred Records, was released on August 25, 2021, and includes a cover of Sepultura's "Troops of Doom."

Martirio is a metalcore band from Santiago, Chile, playing what they describe as evil metalcore with lyrical themes centered on anti-religion and social critique. They released their debut EP Siniestro Presagio I in 2023 through Death Farm Records, followed by Architecti mortis in 2024 and the full-length Los Siete Sellos in 2025 via The Coming Strife Records and Negativ2000.

Marttyrium blend progressive thrash riffing with metalcore structures and death metal heaviness, setting themselves apart within the extreme metal underground of Amapá. The band released "Live Blessed" in 2006 and the album "Depois da Morte" in 2008, with Christian-themed lyrics exploring hope and faith, and appeared on the compilation "Diminishing Diabolical Strongholds" with the track "Bloodpath."

Marturion deliver brutal death metal with explicit Christian lyrical themes, an unusual pairing that places them alongside a small but dedicated scene of faith-driven extreme metal acts. Their self-titled debut EP features seven tracks including "Face A Face," "Drogas," and "Misericordia Eternal Soberana," released independently on CD-R.

Martyrizer played short, abrasive grindcore in the tradition of the Belo Horizonte extreme underground, releasing the six-track "Sick Music To An Extreme World" in April 2014. They also appeared on the compilation "Crushed Vol. II" and performed live that same year at the Metal Punk Overkill III festival before eventually disbanding.

Masacritika is a stoner metal and heavy rock band from Santiago, Chile, formed in May 2015. Drawing on influences including Black Sabbath, Sepultura, and Corrosion of Conformity, they released their debut EP Homónimo in 2017 and their first full-length Thesis Mortem in January 2020, followed by the EP Raza de Kain in 2022, released simultaneously in Chile, France, and Costa Rica.

Formed in 2020 by vocalist Yves Schneider, guitarist Israel Bianchi, bassist Dangelis Britto, and drummer Vinicius Brasil, Masennus fuse death metal's density with grindcore's aggression and tackle themes of existentialism, inner struggle, and social decay. Their debut demo "Phobos Terrorizer" and the follow-up "Disturbing Pandemic Incantations" — which includes a caustic cover of Björk's "Human Behaviour" — both appeared within months of the band's formation.

Mask of Semblant is a deliberately anonymous progressive/melodic death metal outfit whose members have kept their identities hidden since the band's formation. Their debut EP Existence (2017) mapped the Four Horsemen of the Apocalypse across six tracks, while the follow-up Dead Tales (2018) shifted the lyrical lens toward earthly decadence and civilizational rot, both recorded at Socoloski Recordings in Florianópolis.