Atrocity was a thrash metal band from São Paulo, active from 2004 until they split up, operating in the crowded but fertile São Paulo underground thrash scene. The band released material independently, continuing in the tradition of aggressive Brazilian thrash in the style of the São Paulo scene's old-school roots.

Atropelo is a crossover thrash band from Mauá, in Greater São Paulo, whose influences include Brazilian hardcore/thrash veterans Ratos de Porão, D.F.C., and Cólera. The four-piece released their debut album "Mentira Acima de Tudo, Ilusão Acima Todos" in February 2025, recorded at Hells Pass studio in São Caetano do Sul, with lyrics in Portuguese addressing political and social grievances.

Attack Fire is a thrash metal band from Cali, Valle del Cauca, Colombia, founded in 2010 and signed to Tanatofobia Productions. The band built a prolific catalog through the 2010s and into the 2020s, releasing splits and EPs including "Satanic Riffs" (2013) and "Habemus Tenebris Papam" (2014), and appearing on the 2013 Ultrametal Productions compilation "30 Years Of War, Fight, Sweat & Blood." Vocalist and bassist Kristhian Spinal has been a constant presence since the band's founding.

Attomic Soldier is a thrash metal band from São Paulo, Brazil formed in 2017, carrying forward the city's tradition of aggressive, crossover-flavored thrash. Their 2017 debut album "In Mental Prison" is a nine-track assault covering themes of war, insanity, and darkness, showcasing the raw, high-speed aggression typical of the São Paulo underground scene.

Autopsia is a thrash metal band from Pindamonhangaba, São Paulo state, Brazil, one of the country's long-running underground acts with roots stretching back to 1989. Having persisted through more than three decades in the Brazilian extreme underground, they represent the tenacious provincial thrash metal scene that developed outside the major centers of São Paulo and Rio de Janeiro.

Avaken is a power/thrash metal band from Recife, Pernambuco, Brazil, formed in 2020 and part of the northeast's small but growing heavy metal underground. They combine the melodic ambition of power metal with thrash metal's velocity and aggression, an approach that connects them to Brazil's long tradition of technically sharp, high-energy metal.

Aversion is a thrash metal band from Coyhaique, in Chile's Patagonian Aysén region, signed to the Chilean label Rawforce Productions. Their debut full-length Chaotic Dreams (2015), recorded in Coyhaique in October 2012 and mastered at DMG Studio, blends early Scandinavian black metal aggression with driving thrash riffing.

Aversion is a thrash metal band from Coyhaique, in Chile's Patagonian Aysén region, signed to the Chilean label Rawforce Productions. Their debut full-length Chaotic Dreams (2015), recorded in Coyhaique in October 2012 and mastered at DMG Studio, blends early Scandinavian black metal aggression with driving thrash riffing.

Aversus formed in 2012 in Centenario, Neuquén, blending metalcore aggression with thrash metal riffing in a corner of Patagonia that has produced only a handful of extreme acts. The band is signed to Marfus' Records, a Neuquén-based label dedicated to thrash, death, and metalcore from the region.