Castellica is a heavy/power metal band from Paraguaçu Paulista, São Paulo, Brazil, originally founded in 2011 by vocalist Thiago Colavite and guitarists Danilo and Lucas Colavite. Drawing influence from Iron Maiden, Helloween, and Blind Guardian, the band blends classic heavy and power metal with prog metal elements, built around epic riffs, technical solos, and themes of medieval fantasy and human experience. They released their debut full-length album, Moment of Glory, on February 5, 2021, and have performed alongside acts such as Sepultura at the Rock Rio Pardo festival.

Castlevania is a Brazilian power metal band formed in 2004, featuring Gabriel on guitar and bass, Julia on vocals and keyboards, Rayana on guitar, and César on vocals. The band draws heavy thematic inspiration from dark fantasy and the Castlevania video game series, and released their debut demo Castle of Power in 2006, which included a cover of the iconic track "Bloody Tears" from Castlevania II. Their music has been described as epic, free-flowing power/speed metal with fluid and dynamic songwriting.

Castración is a solo project by Santiago-based artist Lucero Guerra, active from 2018, blending raw black metal, harsh noise, and power electronics under the conceptual framework of the body as an instrument of war. The project released Terrorismo Corporal (2018) and Regímenes Carnales (2019), the latter issued as a limited handmade cassette through Octavo Canto, with themes drawn from biopolitics, queerness, and state violence.

Castrivenian is a Brazilian raw black metal project formed in 2024, drawing clear inspiration from the European second-wave scene of the mid-to-late 1990s, particularly early Satanic Warmaster, early Marduk, and Moonblood. In their first year the project released two demos — S.H.T.I. (April 2024) and Eternal Fog's Rebirth (2024, with a cassette release through Wolfkult Religion) — plus a split, demonstrating rapid and prolific output rooted in a harsh, orthodox black metal aesthetic.

Catacomb was a technical death metal band from Buenos Aires, Argentina, whose lineup included guitarist and vocalist Maximiliano Rodriguez, guitarist Joel Poggi, bassist and vocalist Nicolas Becker, and drummer Martin Marques. The band released their debut EP, Unavoidable Internal Process, in July 2019, followed by two further releases in 2023: Where the Numbers End and Paradigm Shift. Their sound paired dense technical riffing with electronic touches and occasional clean vocals, setting them apart from more conventional tech-death acts in the South American underground.

Catacumba is a black metal band from Serra, Espírito Santo, Brazil, formed in December 2003. Their sound blends the primal aggression of South American black metal with the frostbitten atmosphere of the Scandinavian scene, with lyrical themes spanning philosophy, nihilism, and hatred. Their debut full-length album Kratos was originally released in 2010 through Onslaught Records and reissued on CD in 2014 by Fallen-Angels Productions with a live bonus track.

Cataplasma is a thrash/death metal band from Los Ángeles in Chile's Biobío region, originally formed in the early 2000s under the name Carga before settling on their current name. Drawing influence from Chilean legend Dorso as well as international acts like Slayer and Sepultura, the band recorded their debut demo Gore Demencia in 2007 and have remained active in the regional underground metal circuit.

Catharsis Nocturna is a black metal band from Córdoba, Argentina, founded in 2006 by Darker Mysteria on vocals and keyboards, Austhrum Dominius on guitars and programming, and Svart Sjel on bass. The band released their first demo, Genesis Dramatica de lo Difunto, in August 2006, followed by a second demo in 2009, both steeped in themes of darkness, occultism, and nocturnal mysticism. Darker Mysteria and Austhrum Dominius have remained central to the Argentine underground black metal scene, also contributing to collaborations with other regional acts.

Causa Mortal is a heavy metal band from Villa Ballester, in the San Martín district of Buenos Aires Province, Argentina, formed in 2013. The band has performed at Argentine metal festivals including events organized by the Unión de Radios Metaleras, where they have played original material such as "Alumbrado, Barrido y Demencia" and "Privado de la Libertad". They represent the active grassroots heavy metal scene that has long flourished in the greater Buenos Aires metropolitan area.