Aquelarre was a black metal band from São Paulo, Brazil, active in the underground scene and aligned with themes of Satanism, anti-Christianity, and hate in the tradition of South American raw black metal. They contributed a track to the Times of War - A Tribute to M.M.D.C. compilation before splitting up, leaving a small but ideologically committed footprint in the São Paulo scene.

Aqueronte is a black metal band from Curitiba, Paraná, Brazil, part of the city's long-running extreme metal underground. Their approach is rooted in raw, traditional black metal with an uncompromising aesthetic, operating within a regional scene that has produced influential acts like Amen Corner and Blackmass. The band draws influence from classical composition alongside classic and contemporary black metal.

Aquila is a progressive metal band from São Paulo, Brazil, formed in 2009 and active in the city's independent metal scene. Operating without major label backing, they pursue the technically demanding side of progressive metal with a focus on composed, layered arrangements. The band remains active as an independent act within São Paulo's diverse heavy metal community.

Ar da Desgraça is a black metal band from Timbó, Santa Catarina, Brazil, whose name translates roughly to "air of misfortune." Their discography, including Praeludium Tenebras (2017) and Enigmática Perpétua Sinfonia (2020), explores themes of death, hatred, darkness, and melancholy within a raw, underground black metal framework. The duo features Peste Negra on vocals and guitar alongside Algoz on drums.

Arab Zaraq was a Brazilian black metal project active briefly in 2024 before splitting up, leaving minimal documentation in the underground. The name echoes the Qliphothic concept of A'arab Zaraq — the ravens of dispersion — a recurring reference point in occult black metal. Their release exists as a short-lived contribution to Brazil's prolific raw black metal underground.

Arabesco is a solo project from São Paulo, Brazil, formed in 2015 by multi-instrumentalist André Oliveira. The project blends acoustic elements with sludge and doom metal, creating a sparse and heavy sound rooted in the São Paulo underground scene.

Arandu Arakuaa is a folk metal band from Brasília, Brazil, founded by guitarist Zândhio Aquino, who began composing songs in Old Tupi around 2008 and released the band's first EP in 2012. Their name means "knowledge of the sky cycles" in Tupi-Guarani, and their music fuses heavy metal with Brazilian indigenous traditions, incorporating the languages and musical styles of the Tupi, Xerente, and Xavante peoples. Their discography includes the albums Kó Yby Oré (2013), Wdê Nnãkrda (2015), Mrã Waze (2018), and Ainãka (2022).

Arbach was a black metal band from Anápolis, Goiás, Brazil, founded by Emperor Diavolos with the stated aim of combining melody and aggression in the tradition of classic Scandinavian black metal. The band released the demo The Warriors of Pagan Empire (2007), a full-length titled Left Hand Path (2015), and the album Bellum Aeterna (2018) before splitting up.

Arcaico formed in Avellaneda in the greater Buenos Aires area with a lineup of Adrián Saladino on vocals, Miguel Bustos and Demian Yanelli on guitars, Nico Meire on bass, and Federico Gusso on drums. The band released their self-titled EP in February 2013 through Black Eclosion Digital Record Label, a four-track effort that included the tracks "Tu Cabeza Es Mi Bandera" and "Revolución". Their sound blended melodic death metal riffing with aggressive rhythms rooted in the Argentine extreme metal underground.