Ithaca is a heavy/groove metal trio from Buenos Aires, formed in 2020 during the pandemic lockdown, comprising Chino Gorosito (guitar/vocals/piano), Marcelo Bracalente (bass), and Pato Strunz (drums), the latter a veteran of iconic Argentine bands Hermética and Malón. The band is signed to Icarus Music and released their debut album "El Peso Que No Pesa" in September 2024, preceded by three singles — "El Sol Sin Ser," "Susurrando en Tu Mañana," and the title track — released monthly through the northern summer of 2024. The album was recorded at La Nave de Oseberg studio in Buenos Aires with engineer Martín Toledo.

Itium Profanum are a black metal band from Uberlândia, Minas Gerais, Brazil, formed in 2023. They released their debut album Tenebrosos Caminhos Obscuros on January 27, 2023, an eight-track record available independently through Bandcamp. The band operates as an unsigned act within Brazil's underground black metal scene.

Ivory Gates are a progressive metal band from Piracicaba, São Paulo, Brazil, formed in 2000 and named after the Fates Warning song "The Ivory Gate of Dreams." Blending 1970s progressive rock influences with the aggression of heavy metal — drawing comparisons to Iron Maiden, Queensrÿche, and Kansas — the band released their debut album Status Quo in 2005 as a limited edition of 500 copies through Die Hard Records. They have since released a string of albums including The Devil's Dance and Behind the Wall (2023), earning consistent recognition in both domestic and international press.

IxPxCxCxOxCxDxAxBxCxMxAxBxFxOxHx is a brutal death metal and goregrind act from Carabobo, Venezuela, formed in 2016 and since split up. The band released a full-length titled "Infección" in 2016, followed by an instrumental version of the same record and a split in 2017. True to the goregrind tradition, the project operates under an intentionally extreme acronym-based name.

Jack the Joker are a progressive metal band from Fortaleza, Ceará, Brazil, formed in 2014 and comprising Raphael Joer on vocals, Felipe Facó and Lucas Colares on guitars, Gustavo Pinheiro on bass, and Vicente Ferreira on drums. A defining characteristic of the band is their integration of traditional northeastern Brazilian rhythms — maracatu, forró, baião, and frevo — into dense progressive metal arrangements. Their discography includes In the Rabbit Hole (2014), Mors Volta, and The Devil to Pay in the Backlands (2025), the latter inspired by João Guimarães Rosa's landmark 1956 Brazilian novel.

Jackhammer are a power/thrash metal band from Jandira, São Paulo, Brazil. Founded by Leo Axekiller (bass/vocals), Marcelo Barbosa (guitar/vocals), and Bruno Barbosa (drums), the band draws from American thrash metal, German metal, NWOBHM, and hardcore influences. They released their debut album Hard to Be Alive in 2009 and have remained active in the São Paulo metropolitan area's metal circuit.

Jatere is a thrash/death metal band formed in Asunción, Paraguay in 2025. They released their debut demo "La muerte no da risa" in December 2025, a three-track release with Spanish-language titles that showcases their aggressive crossover of thrash and death metal influences.

Jaue is a pagan black metal solo project founded in 2020 by Julián David Trujillo Moreno in El Carmen de Viboral, Antioquia, Colombia, and released through Satanath Records. The project draws on Latin American ancestral thought and released its debut full-length, "Cantos del sur salvaje", in 2023.

Jeff Metal is a neoclassical power metal solo project from Brazil, with all instruments and vocals handled by Jefferson Moura Melo. The project blends classical composition with power metal energy and incorporates Christian lyrical themes. The debut album God Created Rock was released in 2020.