Infector is a death metal band from São Vicente, São Paulo, Brazil, founded in 2000 on the Violent Records label. The band has released multiple full-lengths including "Anguish" (2011) and "Insane Deliriums," and have contributed tracks to several Brazilian metal compilations including the Endless Massacre series (2005–2012) and multiple Gulpian Metal Fest volumes. Their sound addresses themes of death, darkness, and inner turmoil.

Infector Cell is a thrash/death metal band from Cotia, São Paulo, Brazil, playing a fast and aggressive style rooted in the Brazilian underground scene. Their debut full-length album, Cultura Suicida, was released in 2017 through Psicose Records and features ten tracks of high-velocity riffing and pummeling drums. The band returned in 2025 with a second album, Sintam a Nossa Vingança, continuing their output in the Brazilian extreme metal circuit.

Infektus was a death metal band from Timbó, Santa Catarina, Brazil, driven by vocalist and bassist Boris Girardi alongside guitarist Nelson Floriani. The band released a promotional demo titled Devastation in 2005, establishing themselves within the underground death metal scene of southern Brazil. After an extended hiatus the band briefly reunited in 2019 for a live tribute concert at Malária's Metal Fest 3 in their home city.

Inferis is a death metal band from Santiago, Chile, formed in 1998 around guitarist Gonzalo Riveros and a rotating lineup that has included members such as vocalist Rodrigo Manzor and drummer Mauricio Castillo. The band released their debut album In the Path of Malignant Spirits in 2007 through Polish label Old Temple, followed by Obscure Rituals of Death and Destruction in 2013, building a catalog of satanic, blasphemous death metal over their two-decade career.

Infernal Atröz is a black/thrash metal band from Blumenau, Santa Catarina, Brazil, formed in 2022 and rooted in Satanic themes. The band released a debut single-demo in January 2023, followed by the track "A Noite da Caçada" and a full demo in 2024. They operate as an unsigned independent act within southern Brazil's underground extreme metal scene.

Infernal Attack was a black/thrash/speed metal band from Itabaiana, Brazil, featuring guitarist and vocalist Jhonata Hellfire and drummer Julio Hellbutcher. The band released the EP Eternal Desire in 2020 through Sacrifice Records of Portugal as a hand-numbered limited cassette edition of 70 copies. The release was described as "unholy black/thrash from Brazil" and represents the band's key recorded output before their split.

Infernizer is a thrash/death metal project from Caruaru, Pernambuco, Brazil, conceived during the pandemic by Alex Morais, also known from the band Storms. The project released its debut EP Pandementia in 2022, featuring four tracks that draw on thrash, death, black metal, and hardcore influences, with themes addressing pandemic chaos, denialism, and social decay. A second EP, Odiocracia, followed in 2025 with five tracks recorded with producer Daniel Farias.

Inferno Nuclear is an old-school thrash metal band from Belém, Pará, Brazil, formed in 2007 under the name Old School Attack before adopting their current name. Drawing heavily from the Bay Area and German thrash traditions — citing Exodus, Testament, Kreator, and Sodom as key influences — the band features vocalist Wellington Freitas alongside rotating members including guitarist Alexandre Durães. Their 2021 album Diante de um Holocausto was recorded at Chaar Estúdio in Belém and stands as one of their most fully produced releases.

Infestatio is a thrash metal quartet from Jundiaí, São Paulo, Brazil, featuring Rafael "Rafão" Neves on guitars and vocals, Reginaldo "Regi" Iobbi on guitars, Diego "Negão" Necromancer on bass, and André "Fanta" on drums. The band blends old-school and modern thrash approaches with groove-driven riffs and semi-aggressive vocals that draw comparisons to acts like Sadus. Their EP F.Y.A., a five-track release produced by Rafão and recorded partly at Jardim Elétrico Studios, drew favorable coverage from Brazilian metal press on its release.