Forbidden Ideas... is a death/black metal and grindcore band from São Paulo, Brazil, conceived in 2003 by vocalist Bizarro and guitarist Claudio Czarnobai. The band debuted with the demo "Choking With Shattered Glass" in 2005 and went on to appear on the Violent Records compilations Endless Massacre III (2009) and Endless Massacre V (2013). Their lineup also includes bassist Fernanda Czarnobai and drummer João Leonel, with vocalist Diego Parmito joining in 2008.

Forgotten Rites is a black metal band from Buenos Aires, Argentina, formed in 2025. Their debut release, the three-track demo "Time Before Time," appeared in April 2025 and established the band in the Buenos Aires underground black metal scene.

Forgotten Rites is a black metal band from Buenos Aires, Argentina, formed in 2025. Their debut release, the three-track demo "Time Before Time," appeared in April 2025 and established the band in the Buenos Aires underground black metal scene.

Fork of Horripilation is a two-piece black metal band from São Paulo, Brazil, consisting of Liz deSade on vocals and Mario Albino on instruments and vocals, formed in 2022. The duo has released a prolific catalog including the Canti Eretici-released album Folguedo Noturno (2023) and the full-length Mística (2023), drawing on themes of history, paganism, and introspection.

Fosso is a black metal duo from São Paulo, Brazil, formed in 2021, consisting of Pedro Alves on guitar, bass, and vocals, and Victor Miranda on drums. The band released their debut album Solo Amargo in June 2021, a claustrophobic eight-track record recorded and mixed by the duo between March and April of that year.

Fratura is a one-man black metal project from São Paulo, Brazil, created at the end of 2019 by the sole member known as Corposeco. The project channels raw black metal through the lens of crust punk, d-beat, and powerviolence, a hybrid the artist calls "Black-Beat," combining lo-fi sonic violence with antifascist and anarchist themes. The debut album "Corposeco" was released in August 2020 and received a remastered edition in June 2022, which included a cover of Mayhem.

Freyr is a one-man pagan black metal project from Brazil, active since 2022. The project released the debut album "The Blood of Tharsis" in 2022, followed by the full-length "Ancient Pagan Flame" in May 2023, an eleven-track release distributed through Masters of Kaos. A further full-length, "The Death Embracing," followed in 2024, establishing a prolific output rooted in Norse-pagan imagery and raw black metal aesthetics.

Fuego Negro are a black metal/punk band from Valparaíso, Chile, formed in 2013 and active on the Diskordia Records label. Their music sits in the raw, confrontational intersection of black metal aesthetics and punk aggression that has characterized a distinct strain of the Chilean underground scene.

Fulgorious is a Black Metal band from Quito, Ecuador, formed in 2023. The band released the demo "Total Black Metal Cult" in 2025, establishing themselves within the Ecuadorian black metal underground.