One of Them is a Porto Alegre thrash metal outfit whose 2019 album Blind Faith, recorded at Hurricane Studio with producer Sebastian Carsin, brought together vocalist GG Mussi, guitarists Jeff Witt and Ivan Santos, bassist Alexandre Guterres, and drummer Jonas Koehler. The record marked a new phase for the band, arriving roughly a decade after their debut EP I Am One of Them and featuring a Portuguese-language track for the first time.

Operador channel the frustrations of the Brazilian call-center grind into punishing thrash and heavy metal, with lyrics drawn directly from the monotony and dehumanization of telemarketing work. Their 2022 demo "Conexão Call Center" laid out the concept in eight tracks, and the re-recorded version released in 2023 sharpened the riffs while keeping the satirical edge intact.

Oppressus is a thrash metal band from Neiva, Huila, Colombia, formed in 2011. Their debut full-length "Humanidad in Vitro" was released in 2017, with lyrics addressing social and political nonconformity, war, death, and destruction. The band remains active as an independent act on the Colombian underground metal scene.

Orgasmo de Porco bring the chaotic spirit of 1980s American crossover to a distinctly Brazilian underground setting, with Caverna's barked vocals riding atop the palm-muted thrashing of Paulinho and the locked-in rhythm section of Lobo and De Cia. Their 2013 debut "My Mind is a Mess" established their irreverent, full-throttle approach, and 2018's "Voltamos mijados e putos" — later named a Bandcamp Album of the Day — proved they only got tighter with time. Released through Läjä Records and Cianeto Discos, their records sit comfortably alongside classic D.R.I. and Municipal Waste without ever sounding derivative.

Orgia Nuclear cook up a volatile mix of speed metal ferocity, thrash riffing, and black-crust grime, having honed their sound from the early "Caos Total" EP (2013) through to the full-length "Desgastado" (2018), recorded at Darkside Studio in Recife. Sung entirely in Portuguese, their lyrics take aim at social and political targets while the music charges forward with metalpunk urgency. Their split releases and active underground presence reflect a band more interested in raw energy than studio polish.

Orion were founded at the end of 2001 in San Javier, a town in Chile's Maule region, with the stated aim of channeling the spirit of 1980s thrash and death metal. The band released their debut full-length Mysterivm Cosmographicvm in September 2020 through Iron Blood and Death Corporation, recorded and mastered at Equinox Studios in Rancagua, weaving philosophical and ancient-world themes through nine tracks of old-school death/thrash.

One of the most enduring crossover/thrash acts from the Serra Gaúcha region, Ossos fuse the aggressive tempo of hardcore with heavy thrash riffs in a style forged through decades of relentless live activity. Their 2018 album Caos em Mim was followed by Contos do Necrotério, cementing a reputation as one of southern Brazil's most committed names in the crossover underground.

Originally a Kreator cover project called Hordes of Aggression, Outlanders reoriented toward original material after changing their name in 2011 and spent years honing a Bay Area-influenced thrash attack. Their debut album From Chaos to Extinction, produced by Thiago Bianchi at Fusão Studios and featuring guest vocals from Chuck Billy of Testament, finally arrived after years of recording and stands as a focused statement of old-school thrash conviction.

Formed in Teresina around 2017, Overdose Brain play a ferocious brand of speed/thrash metal sung in Portuguese, drawing on the Brazilian underground tradition of acts like Flagelador and Cemitério. Their 2020 EP Exército Metal, recorded with vocalist Thiago Araújo, guitarist Cláudio Costa, bassist Alisson Barros, and drummer Wanderson dos Anjos, showcases cutting riffs and an uncompromising approach rooted firmly in 1990s aggression.