Cicuta was a death metal band from Santo Antônio de Jesus, Bahia, Brazil, that has since split up. The duo — comprising Pedro Rodrigues on bass, synths, and vocals, and Sérgio Gregório on drums — released a self-titled album with nine tracks. Their music represented a raw, underground strain of Brazilian death metal from the interior of Bahia.

Clamatorius is a black/death metal band from Goiânia, Goiás, Brazil, originally active from 1999 to 2005 under their own name after an earlier incarnation as Postumus (1998–1999). The band is notable for fusing extreme metal with Christian lyrical themes and released the five-track album "Consummatum Est" through Blackened Label Records.

Clan dos Mortos Cicatriz is a death-punk band from Curitiba, Paraná, Brazil, blending raw black metal, death metal, and hardcore punk into what the underground has called "nekro-hardcore." The band released their debut album "Técnicas de Morte" in March 2025 via Sentient Ruin Laboratories, a 15-track, 25-minute record described as a grim manifesto drawing imagery from slums, prisons, morgues, and war zones.

Clemency is a Christian death metal band from Londrina, Paraná, Brazil. The band released the demo "Satan's Funeral" (1998) and the full-length "Spiritual Domination" (1999), the latter reissued in 2019 via Warriors Records and Eirene Records. Their lyrical themes centered on Christianity, distinguishing them within Brazil's death metal underground.

Coagulo was a death metal band from San Juan, Argentina, formed in 2015 and later split up. The five-piece lineup featured Julián Ibars on vocals, Martín Manrique and Julio Rosales on guitars, Elías Vega on bass, and Daniel Fernández on drums.

Coldblood is a death metal band from Rio de Janeiro, Brazil, originally formed in 1992, with themes rooted in Satanism and anti-Christianity. After two break-ups and a permanent reformation in 2005, the band released their debut full-length "Under the Blade I Die" in 2007, followed by "Chronology of Satanic Events" (2013) and "Indescribable Physiognomy of the Devil" (2016), the latter released through Selfmadegod Records.

Confounded is a death metal band from Recife, Pernambuco, Brazil, formed around 2013 and active in the northeast Brazilian extreme metal scene. The band plays heavy, groove-inflected death metal and maintains a presence on Bandcamp and Instagram under the handle @confoundedband.

Conjurador is a black/death metal project from Porto Alegre, Rio Grande do Sul, Brazil, formed in 2021 with themes centered on Satanism and occultism. The band released multiple demos in their first year of activity and followed up with the EP "Conjurers of the Infernal Key" in 2022.

Contemptible Ruins is a death metal and crust punk band from Brasília, Brazil, formed in 2021. Their sound blends stenchcore and death metal influences, drawing comparisons to the rawer end of the crust/death spectrum. The band has released several recordings including a self-titled debut (2021), "The Radicalization of Human Pathology" (2022), and "Point of No Return" (2023).