Alcoólica was a thrash metal band from Santos, São Paulo, formed in 2013 and part of the port city's underground metal scene alongside acts like Chemical Disaster. The band released sessions through their Bandcamp page before eventually splitting up, representing Santos's contribution to the broader São Paulo state thrash underground.

Aleacion was a heavy metal band from San Juan, Argentina, active through the 1990s under the name Cromagnon before adopting the Aleacion name. The band released the EP "El combatiente" in 1995 and documented their live performances on the 1996 release "Vivos en el Auditorio Juan Victoria".

Alekto is a death/groove metal band from São Paulo, Brazil, formed in 2014 and active in the city's underground extreme metal circuit. The band combines the heaviness of Brazilian death metal with the mid-paced rhythmic punch of groove metal, drawing on a tradition that runs deep in São Paulo's metal scene. They have an online presence at alektometal.com and maintain an active following within Brazil's groove and death metal communities.

Alerta Vermelho was a crossover/thrash band from Belo Horizonte, Brazil, formed by veteran underground musicians who swapped roles to channel raw punk and thrash energy. Their 2024 EP "Zero" — a six-track, 15-minute release on Metalpunk Overkill Records — fused punk aggression with metallic weight and was recorded entirely in Portuguese, arriving on limited-edition orange cassette. The band drew from a lineage of Belo Horizonte crossover acts and influences ranging from Misfits and Hüsker Dü to Brazilian punk outfits like Replicantes and Plebe Rude before splitting up shortly after the release.

Alexandre Rocha is a solo progressive metal project from Bauru, São Paulo state, Brazil, launched in 2021 after Rocha spent years composing and playing in local metal bands. His debut album "Viewpoints" (2021) was fully performed, produced, and recorded by Rocha at Mister Rec Vintage Studios in Bauru, featuring seven tracks of technically oriented progressive metal with a strong emphasis on composition and dynamics. The project reflects a one-man approach to the genre that prioritizes melodic depth alongside technical proficiency.

Algea is a depressive suicidal black metal (DSBM) project from Curitiba, Paraná, Brazil, formed in 2021 out of an earlier project called Blackheart that ran from 2018 to 2021. The band is a prolific independent act with multiple releases including "Sentimentos Sepultados", "Shades of Depression", "Culto das Trevas", and "Voices", all available on Bandcamp, exploring themes of depression, isolation, and suicidal ideation in the raw and minimalist tradition of the subgenre. Algea remains unsigned and operates entirely within Curitiba's underground black metal underground.

Algoz Profanador is a black/thrash metal band from São Paulo, Brazil, playing in the raw and chaotic tradition of Brazilian black-thrash that traces its roots to acts like Sarcófago and Vulcano. Their 2019 album "Vagando nas Sombras do Caos" is a 10-track assault drawing on occult imagery, nihilism, and philosophical darkness, with track titles like "Before the Abyss" and "Devastation Without Mercy" anchoring their sound in the most aggressive end of the São Paulo underground. The band remains active and independent.

Alianza was a Buenos Aires heavy metal project formed by vocalist Adrián Barilari and keyboardist Hugo Bistolfi following their departure from Rata Blanca in the early 1990s. The duo released three albums — "Sueños del Mundo" (1994), "Alianza" (1997), and "Huellas" (1999) — blending melodic heavy metal with the symphonic keyboard work that defined Bistolfi's style.

Alicercius is a melodic power metal band operating across Rio de Janeiro and São Paulo, Brazil, active since 2022 under the current lineup. The band's name derives from the Latin word for "foundation" and reflects a Christian metal identity, situating them within Brazil's long-running tradition of faith-driven power metal. They deliver soaring melodic riffs, double-bass rhythms, and anthemic songwriting in the vein of European power metal, with an earlier incarnation of the band having released the album "Guerreiros Celestiais" (Heavenly Warriors).