Ashes of Mirra is a progressive metal band from Rio de Janeiro, formed in 2023, featuring vocalist Weslen Amorim, guitarists Fabio and Sebastian Garcia, and bassist Roberto Ribeiro. The band released their early material on Bandcamp, with tracks including "The Pangea Puzzle," "Limit," and "Speechless," pointing toward a sound that favors compositional depth within the progressive metal tradition.

Ashtoreth is a doom/black metal band from Florianópolis, Santa Catarina, whose music is steeped in the mythology and folklore of the city known as the "island of magic." Their 2022 debut album Bruxólico — released on Dejeto Sonoro Records — weaves distorted guitars, unconventional percussion including a zither, and varied vocal approaches into six tracks across 40 minutes, drawing on local witchcraft legends and the poetry of Symbolist writer João da Cruz e Sousa. The album is envisioned as the first part of a trilogy.

Asilo was a Buenos Aires sludge, drone, and doom metal collective that built a catalog of slow, crushing releases across the 2010s, including the split with Neh Czneg (2013), Comunión (2014), and Desintegración (2019). Their approach leaned toward extended, corrosive compositions that placed them firmly within the heavier end of Argentina's underground doom scene.

Asper is a heavy metal band from Porto Alegre, Rio Grande do Sul, active since 2018 in one of Brazil's most established regional metal scenes. Porto Alegre has long been a hub for traditional and extreme metal in southern Brazil, and Asper operates within that tradition as an independent act.

Asphalt Grieving is a black/death metal act from Santiago, Chile, who debuted in January 2024 with the EP "Lack of Certainty," released by Black Legion Records as a limited clear CD edition of 300 copies worldwide. Later in 2024 they released a second EP, "Transgression of the Quantum Self: Tertiary Magnitude," featuring session drums by Krzysztof Klingbein and three tracks totaling approximately 24 minutes.

Aspidis is a dissonant black/death metal band from Jaraguá do Sul, Santa Catarina, founded in 2012. Their 2017 EP Reborn From Darkness and their more recent album Intruding Voices (2025) reflect a dense, abrasive approach to the genre with roots in the dissonant death metal current popularized by acts like Ulcerate and Gorguts.

Ass Flavour is a death/grindcore band from Vila Velha, Espírito Santo, active since 2005 and known for gore-drenched splatter-death metal in the tradition of Carcass, Pungent Stench, and Cannibal Corpse. Their 2015 album Dirty Procedure showcases ultra-fast drumming and multi-timbred growling vocals alongside pathological themes, and members have since branched into related projects including the death/black metal act Impugnant.

Assassinato is a raw black metal band from São Paulo, operating in the Brazilian black metal underground since 2018. Their Bandcamp catalog includes releases such as Hellarsal, Spiritual Rites to Extinction, and Black Iron Paganism, titles that signal a commitment to orthodox, lo-fi black metal aesthetics rooted in occult and adversarial themes.

Assault is a speed/thrash metal band from Vitória da Conquista, Bahia, formed in 2021 and playing in the aggressive tradition of Brazilian thrash metal. Operating out of the interior of Bahia — a state better known for axé and forró than thrash — the band channels the raw, high-tempo aggression of the genre with themes rooted in misanthropy and anti-religious sentiment.