Inglorious Basterds is a heavy and power metal band from Indaiatuba, São Paulo, Brazil. The band released their debut full-length album, Inglorious Hearts, in 2023, a five-track record praised for its melodic riffs, cohesive bass work, and polished production.

Inheritours is a death metal band from Caxias do Sul, Rio Grande do Sul, Brazil, formed in 2014. The band is noted for their drummer Mateus Michelon, who became recognized beyond the local scene and went on to join the band Losna.

Inhibidor is a heavy metal band from Rosario, Argentina, formed in 2020 by Alberth Páez. Their debut album "Vértigo" was released in January 2022 and featured guest contributions from members of established Argentine metal acts including Horcas, Tren Loco, and Serpentor, reflecting the band's connections across the country's heavy metal scene. The album includes a cover of the classic RIFF song "En la Ciudad del Gran Río" alongside original material.

Inhuman Entity was a brutal death metal band from southern Chile, formed around 2016–2017 by vocalist Raul E. Gonzalez, guitarist Gonzalo Sanchez (also of Carniceria Grotesca), and drummer Manu Acevedo (also of Hail Caligula). The band released their sole EP Kingdom of False Divinity in May 2017 through Rotten Music, a four-track slab of brutal death metal with goregrind elements drawing on both old-school and contemporary influences from the international extreme metal underground.

Inhuman Penitence is a death metal band from São Paulo, Brazil, formed in 2018, featuring vocalist Gabi Crust Force, guitarists Diego Noise and Renato Gimenez, bassist Nilson Slaughter, and drummer Daniel Vecchi. The band has released tracks including "Cave of Forgotten Dreams" and "Lessons of Darkness", establishing a five-piece lineup rooted in the São Paulo extreme metal scene.

Initiate Decay is a death metal band from Esteio, Rio Grande do Sul, Brazil, active since 2018 and rooted in the brutal and technical ends of the genre. Their debut release, Awaken the Extinction (2018), established the project's dense, aggressive sound, with the band describing their approach as combining brutality with technical complexity. The lineup has included Aires Trajano and Alexandre Graessler among its members.

Inmemorial is a doom/death metal band from Lima, Peru, who began exploring their sound in the early 1990s, releasing their first demo "Melodías Moribundas" in 1996. Their music explores themes of melancholy, pain, wrath, and the depths of human emotion. The band has released two demos and two EPs, including the 2017 EP "Clamor y Silencio."

Inner Abyss is a black metal and dungeon synth project from Ushuaia, Tierra del Fuego, Argentina — one of the southernmost cities on Earth — formed in 2011. The band released their self-titled debut album in September 2011, followed by the EPs "Outer Space" (2014) and "Totengesänge" (2015), and the album "Don't Dream It's Over" in 2023. Their catalog blends raw black metal with atmospheric synthesizer work, and the project maintains an active Bandcamp presence.

Inner Branch is the solo death metal project of musician and composer Mario Bello Araneda from Carahue, Chile, in the Araucanía region. The project released the album Espejo de confusión, recorded at Mario Bello's home studio and mixed and mastered at Neurotic Records in Temuco.