Ascoroso is a goregrind and death metal band from Sousa, Paraíba — a notable outpost for extreme metal in Brazil's Northeast region. Formed in 2020 and fronted by vocalist Capiroto, the band has been prolific in the split format, releasing material alongside acts like Vítimas do Crack and Murgo, with Portuguese-language track titles dealing in visceral gore imagery. They appeared on the 2020 international compilation "The Great Blood Feast Vol. 1."

Asedio is a death/thrash metal band from Ecatepec, State of Mexico, formed in 2007 with a mission of delivering extreme metal sung entirely in Spanish. The band built a catalogue of multiple studio albums and EPs including Somos Nada (2009), El Origen de Todos los Males (2012), and several later releases, establishing themselves as a consistent voice in Mexico's Spanish-language extreme metal underground. Their sound blends melodic death metal elements with thrash aggression, with lyrics addressing personal struggle and social themes.

Asense is a progressive death metal and metalcore band from Santiago, Chile, formed in 2009, whose discography spans three albums: "The Cold Nightmares of Belphegor: Tempest in Seven Regions" (2009), "Cellarius" (2014), and "tō kyō - o da i ba" (2018). Their lyrics address sociopolitical themes and complex philosophical ideas, and all three records are available independently on Bandcamp.

Asfixia is a thrash metal band from Campinas, São Paulo, one of Brazil's most active metal cities outside the capital. The band operates in the old-school thrash tradition, drawing on the deep legacy of the Campinas and São Paulo underground scenes that have produced dozens of aggressive thrash acts since the mid-1980s.

AshBürn is a power metal band from Vitória, Espírito Santo, formed around 2014–2015 and led by vocalist Heron Ribeiro. The band released the album "You Can Not Kill What Can Never Die" in 2020, recorded and produced by Thiago Bianchi at Fusão VM&T Studios in São Paulo, and has shared stages with established Brazilian metal acts including Almah (featuring ex-Angra vocalist Edu Falaschi) and Noturnall.

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.

Ashriel is a one-person Atmospheric Black Metal project from Bogotá, Colombia, active since 2016 with a hiatus between 2018 and 2020. The project released the demo Spectris in 2016 and the single Memories Rises from Dead River in 2018, exploring themes of death, emotions, personal struggles, and nature.

Ashtar was a progressive folk metal band from Rio de Janeiro that blended Celtic folk melodies, violin, and clean female vocals with a doom-inflected metal foundation. Originally formed in 1997 and known for their 2002 debut album Urantia — a record shaped by esoteric and Irish/Scottish lyrical themes — the project went through multiple lineup changes before dissolving in 2015.

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.