Gangrena are a death metal band from Chillán, Ñuble, Chile, formed in 2005 and affiliated with Australis Records. Their 2020 album "Oscuro Tormento," described by the band as their fourth full-length and brutal from start to finish, cemented their standing as one of the more enduring acts in the Chilean provincial death metal underground.

Gangrena Gasosa is a thrash metal and crossover band from Rio de Janeiro, Brazil, who brand their style as "Saravá Metal" — a fusion of metal and hardcore with Umbanda and Afro-Brazilian religious imagery. On stage, each member portrays a specific Afro-Brazilian deity or spirit, making the band's live presentation unique within the Brazilian metal scene. The band released the LP Welcome to Terreiro in 1995 and has remained active for over three decades, issuing the album Figa of the Dark in 2024.

Gargola is a heavy/power metal band from Virreyes, Buenos Aires, first active from 1995 with themes centred on social denouncement and political injustice. The band contributed the track "Battle Hymn" to the 2004 Argentine Manowar tribute Muerte al Falso Metal and "The Ripper" to the 2005 Judas Priest tribute A Tribute to the Priest.

Gargullas is a death metal band from São Caetano do Sul, São Paulo, Brazil, originally formed in 1989 before splitting up in 1998. The band released the EP Secrets of Eternity in 1993 and issued a self-released 7" in November 1992. Members included vocalist Rogério Ribeiro, guitarists Alexandre and Emerson Poletti, bassist Fernanda, and drummer Cristiano Delboni.

Gates of Holocaust is a black metal band from João Pessoa, Paraíba, Brazil, formed in 2015. The band released the six-track album Void on July 28, 2015, featuring material originally recorded in João Pessoa in 2012. Their music operates in a raw, underground black metal vein.

Gateways to Oblivion is a doom metal project from São Paulo, Brazil, formed by Mateus Henrique. The project released multiple albums in rapid succession, including Withering in the Dark (May 2022), Subterranean Faith (August 2022), The Aquatic Witch (November 2022), and The Arcane Equinox (February 2023). Their sound explores dark, atmospheric doom in the tradition of underground Brazilian doom metal.

Gatica are a thrash/grindcore band from Rosario, Argentina who launched in 2020 with the 15-track debut Matando Chetos (May 2020), followed swiftly by the equally frenetic Barbarie mata galán (March 2021). Both records blend politically charged lyrics with short, high-speed songs in the tradition of extreme crossover grindcore.

Geisterseher is a one-man experimental black metal project from Paraná, Brazil, operating as a side project of Draugur, the sole member of the main band Paarthurnax. The project released the four-track EP "Fragmento Espectral" in April 2020, weaving atmospheric and experimental textures across tracks including "Aldebaran," "Ad Hominem," and "The Void."

General Kroll are a crossover thrash band from Rosario, Santa Fe, Argentina, formed in 2015. Their seven-track Demo Ensayo 2015 was recorded, mixed, and mastered by Augusto Brasseur at Sala HUM in Rosario and released in June 2015, documenting an early sound built around fast, hardcore-inflected riffs and sardonic song titles.