Mantra Cornuta is an independent metal band from Medellín, Colombia, formed in 2015. The band blends traditional heavy metal with Latin influences, electronic elements, and metalcore intensity, and has released two EPs — Filth (2015) and Scorn (2018) — alongside several standalone singles.

Mantra Heavy Metal is a heavy metal band from Buenos Aires, formed in 2001 by vocalist Eduardo Paredes, guitarist Walter Sobrero, bassist Ramiro Cora, keyboardist Luis Cosenzo, and drummer Ariel Behrend. The band self-released a seven-track demo in 2003 and returned a decade later with the full-length Perder Para Ganar in 2012.

Mar de Grises was formed in Santiago, Chile in 2000, developing a death/doom sound that incorporated post-rock, ambient, and progressive elements into their dense compositional framework. Their debut The Tatterdemalion Express (2004) established them as a significant voice in South American doom, followed by Draining the Waterheart (2008) and Streams Inwards (2010), the latter named the top doom metal album of 2010 by Metal Storm's user base. The band dissolved in 2013 but announced a reunion in 2024, their catalog standing as one of the most ambitious in Latin American extreme metal.

Mar Muerto is an experimental metal band from Antofagasta, Chile, formed in 2017. Rooted in heavy metal, the band incorporates experimental touches spanning classical music, progressive structures, and black metal influences. Their 2020 EP Shub-Niggurath, a seven-track release drawing on Lovecraftian themes, stands as their primary recorded output to date.

Formed as a supergroup drawing from well-known names in the national underground, Marabô features vocalist Felipe Chehuan (formerly of Confronto and Cabeçudos), guitarist Davi Baeta, bassist Paulinho Coruja, and drummer Henrique Pucci. The band channels heavy groove and metalcore through dense riffs and politically charged lyrics, as heard on the single "Estacas," which was recorded, mixed, and mastered by Baeta and Pucci themselves.

A one-person DIY project blending thrash, hardcore, and grindcore with a deliberately absurdist sensibility, Marafo de Exú debuted in 2016 with the 16-track album "Diabólico Alcoólico," a chaotic slab of short, fast songs delivered with raw, lo-fi ferocity. The project also released a live recording from Destroy Music Now Fest 3, capturing the same unfiltered intensity in a live setting.

Marbas Valfoerd is a Buenos Aires black metal project that released its debut full-length Primus Omen Op.1 on February 22, 2021. The project also collaborates with fellow Argentine musician Blatt Siro under the name Argiaren, which issued the instrumental release Fragmento 1 in April 2022.

Guitarist Marcelo Souza spent six years in the thrash metal band Attomica (2014–2020), touring across South America before launching a solo instrumental career that draws on metal, neoclassical, blues, and progressive fusion. His 2021 album "Human vs Machine," released through Oversonic Music, features guest appearances from vocalists Mário Pastore and lap steel guitarist Luís Carlini, and explores the tension between human expression and digital dependency.

Marcelo Yakko is an Argentine bassist and composer from Villa Gesell whose output spans more than 15 instrumental albums blending progressive metal, jazz fusion, and Latin influences. His 2018 album Nevada Mortal is a progressive metal concept record inspired by the classic Argentine sci-fi comic El Eternauta, and his 2024 release Yakkosonics features a roster of international collaborators including guitarist Alex Suarez and drummers Nicolas Fernandez Mac Loughlin and Martin Zamorano.