Corrossive is a death metal band from Buenos Aires, Argentina, formed in 2015. They released the demo Overcome the Darkness in 2016 before issuing their debut full-length The Great Beyond in 2021, an eleven-track record that draws on death, doom, progressive, and thrash metal influences.

Corruption of Soul was a technical death and thrash metal project from Belém, Pará, Brazil, formed in 2022 by Ivan Guilherme, known as Sodomizer. The project, which used programmed instruments, produced a self-titled eight-track album before splitting up. Belém has a historically notable place in Brazilian heavy metal, being the home city of Stress, who released the country's first heavy metal LP in 1982.

Corsário is a heavy metal and progressive metal band from Belém, Pará, Brazil, formed in 2016. The band describes itself as "Heavy/Prog da Amazônia para o Mundo" (Heavy/Prog from the Amazon to the World), blending traditional heavy metal with progressive elements rooted in the Amazon region's musical identity. They remain active and release music through Bandcamp.

Corubo is a black metal and ambient band from Ji-Paraná, Rondônia, Brazil, who describe their sound as "Indigenous Black Metal," weaving atmospheric black metal with indigenous Brazilian folk influences, field recordings, and lyrics in languages including Guaraní, Nheengatu, Tupi, and Portuguese. Their music explores the history and resistance of Brazil's indigenous peoples, drawing on themes of colonisation and the Amazon's First Nations cultures. Their 2021 album Ajuricaba is centered on the Manaus people's wars of resistance against Portuguese enslavement in the early 18th century, named after their leader Ajuricaba.

Corujas is a raw black metal band from Catanduva, São Paulo, Brazil, active since 2013. The band's lyrical themes center on nature and birds — "corujas" means owls in Portuguese — placing them within the tradition of Brazilian raw black metal acts that draw on the natural world for imagery. They release music independently through Bandcamp.

Cosecha Lagrimas is a melodic death metal band from Mar del Plata, Argentina, drawing clear influence from the Scandinavian melodic death tradition — their Bandcamp catalog includes the tracks "Corazón Flamígero" and "Animus Meminisse Horret", and in 2016 they released a live EP alongside a recording of Sentenced's "May Today Become the Day". The band celebrated their seventh anniversary with a live performance in Mar del Plata in 2014, marking them as one of the longer-running melodic death acts on Argentina's Atlantic coast.

Cosmic Abyss is a progressive thrash metal and crossover band from Brasília, Distrito Federal, Brazil. They combine the technical aggression of thrash metal with crossover punk energy, and their thematic focus on cosmic and futuristic subjects sets them apart within the Brasília underground scene. The band is independent and active.

Cosmic Rover is a stoner metal trio from São Paulo, Brazil, formed by drummer and vocalist Edson Graseffi (formerly of Panzer), bassist Rodrigo Felix, and guitarist Xande Saraiva of Baranga. The band blends stoner rock, heavy metal, and southern rock influences, recording their albums live in the room to capture an organic 1970s feel. Their second full-length album, Heavy, was released in December 2021 via Abraxas Records.

Cosmic Sepulcher is a death/doom metal solo project from Euclides da Cunha, Bahia, Brazil, formed in 2024 by multi-instrumentalist Athayde Neto, who handles all instruments, vocals, recording, and production. The project draws on cosmic horror and the Cthulhu Mythos for lyrical inspiration, crafting dense, funereal compositions that explore dark fantasy and existential dread. Neto is also active in the bands Wiseblood, Töhil, and Adumbrall.