Abissal was a black metal band from São Francisco do Sul, Santa Catarina, in southern Brazil. Operating from 2018 until their dissolution, the band played raw, underground black metal with themes rooted in darkness and anti-Christianity, in the tradition of the Brazilian underground extreme metal scene.

Abjeto is an experimental black metal project from São Paulo that began as a solo venture by guitarist and vocalist Mario Albino before evolving into an improvisation trio with the additions of Rafael Lennert and Alice Duarte. Their approach fuses raw and atmospheric black metal with improvised, free-form structures rooted in mysticism and introspection. The band has released several recordings through Bandcamp including Conclave, Dialética do Caos, and Argumento VI.

Able to Return is a melodic death and groove metal band from Santarém, Pará, in the Brazilian Amazon — a notably isolated location for extreme metal. Formed in 2019, the band merges Scandinavian-influenced melodic death metal with groove metal heaviness, representing a growing extreme metal presence in Brazil's northern interior.

Abominador is a thrash/black metal band from Santa Mariana, Paraná, formed at the end of 2009 with the explicit aim of making raw, stripped-down extreme metal entirely in Portuguese. Drawing from the Brazilian bestial black/thrash tradition, the project released a demo in 2010 and has continued operating in the underground since, favoring aggression and directness over production polish.

Abomination is a thrash metal band from Brasília formed in 2015, operating in the underground tradition of the Brazilian federal capital's metal scene. Playing aggressive, no-frills thrash metal, the band carries on the South American extreme thrash legacy in a city better known for bureaucracy than brutality.

Abominatus is a black metal band from Garanhuns, Pernambuco in Brazil's northeast, formed around 2001 under the name Melancholic before adopting their current identity. The band plays satanic and anti-Christian black metal and released the album Kill the Christians in 2011, featuring symphonic elements layered over orthodox black metal hostility.

Abominor was a black metal band from Barra Mansa, Rio de Janeiro, active from 2015 until their split-up. The band played dissonant, uncompromising black metal and released recordings including Oration MMXVI and Source of Chaos during their run in the Brazilian underground.

Aborior was a black metal band from Brasília, active during the mid-2000s to around 2010. The band played raw black metal with anti-Christian lyrical themes, part of a wave of underground extreme metal acts that emerged from Brazil's federal capital in the 2000s decade.

Aborticide was a brutal death metal band from Sete Lagoas, Minas Gerais, formed in 2009. The band played in the tradition of Brazilian brutal death metal with themes of demonology and darkness, and contributed to the compilation Warriors of Morbid Moon Vol. 2 before disbanding.