Grind Convulsion are a brutal death metal and grindcore band from Santa Fe, Argentina, signed to Inhuman Therapy Records. Their 2014 EP "Rebirth of Blood" includes tracks such as "Putrefaction In Crescendo," "Grotesque Deformity," and "While I Use Your Remains," along with two live recordings from the GFF '13 festival. The band also contributed tracks to the Argentine extreme metal compilations "Argentina Extrema Vol. 2" (2015) and "8 Ways to the Internal Rot" (2016), with Pat on bass, Juan C. on guitar, and Ismael on drums.

Grindeals is a grindcore and death metal band from Recife, Pernambuco, Brazil, formed in 2020. The independent act explores lyrical themes of violence, psychological struggle, death, and addiction within a brutal extreme metal framework.

Grinding Reaction is a thrash metal and hardcore band from Diadema, in greater São Paulo, Brazil. The band blends old-school and new-school hardcore with thrash and groove metal while tackling political and social themes, and has released material including the EP Tempo, Persistência e Fúria and a full-length album featuring fifteen original tracks.

Grisvelos is a one-man black/death metal project from Osorno, Los Lagos, Chile, created by Alfredo Torres, who also plays bass and backing vocals in the black/thrash band Degotten. The project debuted in August 2020 with the full-length "Desperatio," a nearly 50-minute album drawing from the influence of Morbid Angel, Immolation, and Marduk while channeling the band's description of Osorno as a cold, decadent city into music that blends ferocity with melodic, nostalgic atmosphere.

Grobr. is a solo doom metal project based in Jundiaí, São Paulo, Brazil, formed in 2025. The project is entirely self-produced by a single multi-instrumentalist who handles everything from composition to mixing, and has released the album Doomsday Clock alongside the standalone track Aether.

Grosstracktor is a groove metal band from Lota, Bio-Bío, Chile. The band's name references the Grosstraktor prototype medium tanks built by German manufacturers Rheinmetall-Borsig, Krupp, and Daimler for the Weimar Republic in violation of the Treaty of Versailles.

Guerreiros Headbangers is a black/thrash metal band from São Paulo, Brazil, who released their debut album Eras em Guerras, Mundo em Caos in 2024 along with singles including Memento Mori and Noite Através da Noite. The band has shared the stage with internationally recognized acts such as Bulldozer, Enforcer, Skull Fist, Nocturnal, and Witchtrap.

Gulag is a Brazilian avant-garde and depressive black metal solo project based in São Paulo, with all instrumentation, vocals, and composition handled by Matheus Cornely. The project released Fantasia in 2023, described as a departure toward sober black metal and dungeon synth aesthetics, incorporating a cover of Nocturnal Depression's "Nostalgia." The project also released Death and Its Roses and the Black Flag single on Bandcamp.

Gurkhorg is an atmospheric black metal band from Coquimbo, Coquimbo Region, Chile, formed in 2024. They are one of several atmospheric black metal acts active in the Coquimbo scene alongside local bands such as Aume and Sunvher.