Arkanus is a Brazilian heavy metal band formed in 1994 and active since the mid-1990s underground scene. The band built their catalog through a series of self-released demos including Black Out (1999), Six Feet Under (2000), and Mysterious Places (2002), demonstrating a long commitment to independent heavy metal in Brazil. Despite years of activity, they have remained a consistently underground act without major label backing.

Arkhaikus was a thrash metal band from Presidente Prudente, São Paulo, Brazil, active from 2010 until their split-up and operating under several earlier names including Slackerness and Metaldier before settling on the final moniker. The band's lyrical themes centered on warfare, evil, and metal culture, fitting squarely within the aggressive thrash tradition of the Brazilian interior. They documented their live activity with a bootleg recording from a 2011 show in Santo Anastácio.

Arkhôn Tôn Daimoniôn is a black metal band from Salvador, Bahia, Brazil, founded in 1995 by vocalist Duxgor and guitarist Grim Abra-Melim Offilatrus, making them one of the longer-running underground black metal acts out of Brazil's northeast. Rooted in explicitly Satanic and blasphemous themes, they released the demo Sacrum Ex Operam Dare in 1998 and Visions of the Apocalypse in 1999, both circulated in the tape-trading underground. The band debuted live at the Occult Ritual of Fire Festival in December 1996 and has continued performing into the 2020s.

Arkillator is a thrash metal band from Quito, Ecuador, originally formed in 2017 under the name Nightmare before adopting their current identity. The two-piece outfit released their debut EP Miseria Social in January 2026, a five-track effort that delivers straightforward thrash in the tradition of the genre's classic era. They operate independently and perform live in the Quito metal scene.

Armagedon is a heavy metal band from Florencio Varela, Buenos Aires, formed in 1991 and active across several decades with a catalog of socially charged material. They released their debut self-titled album through independent label Altar Records and followed it with "Ecología" in 1995, also appearing on the 1997 Argentine metal compilation "Nuevos Guerreros" released by Yugular Records.

Armoured Knight is a heavy/speed metal band from Peñaflor, Chile, active since 2012, whose lineup has centered on guitarist Cristian León alongside vocalist José Tapia and bassist Christopher Falk. They built their catalog across three EPs — "Prophecy of Tomorrow" (2013), "Ashes of Glory" (2017), and "The Sacred Flame" (2020) — before releasing their debut full-length "The Quest for the Sacred Melody" in October 2025 through German label Dying Victims Productions.

Aroma de Saturno is a doom, sludge, and stoner metal band from Blumenau, Santa Catarina, Brazil, formed in 2018. They occupy the slower, heavier end of the Brazilian metal underground, releasing their self-titled EP and the track Ponto Sem Retorno through Bandcamp. Blumenau's German-immigrant heritage and industrial past give the city an unusual cultural backdrop for the kind of heavy, atmospheric metal Aroma de Saturno pursues.

Arrastado is a stoner and doom metal project from Brasília, Brazil, formed in 2018 and built around home recordings under the name that translates roughly to "dragged" in Portuguese — apt for the slow, crushing tempos the band favors. Their releases include the album Isso Também Será Esquecido (This Too Shall Be Forgotten) and Hinos do Esquecimento, both available on Bandcamp and consistent with the heavy, fuzz-driven doom aesthetic. The project's DIY approach and introspective Portuguese titles reflect the broader character of Brazil's independent stoner-doom underground.

Arrebol is a progressive metal project from Santiago, Chile that has released material including the album "Simplicity of the Moment" (2023) and the EP "Four Leagues Away" (2024), the latter issued as a limited digipack of 66 copies. The project's output blends progressive metal with atmospheric and extreme metal influences.