Iron Monkey are a legendary sludge/doom metal band from Nottingham, formed in 1994 and signed to Relapse Records. Their crushing sound of fuzzed-out guitars and misanthropic snarls has made them vanguards of the sludge doom genre across releases like 2024's Spleen & Goad.

Iron Pike is a sludge/doom metal act from Malmö, Sweden, active since 2015 and channeling monolithic heaviness through its doom metal framework. The project delivers oppressive, glacially paced compositions.

Iron Sect is a sludge/stoner/doom metal band from Saint Petersburg, Russia, active since 2024 and delivering crushing, fuzz-laden heaviness where doom's oppressive weight meets stoner metal's hazy grooves. The project channels low-end power and psychedelic atmosphere.

Iron Slug is a German sludge metal band formed in 2024, dealing in the thick, tar-heavy riffs and crushing slowness that define the genre. The band delivers oppressive sonic weight with a deliberate, steamrolling approach.

Iron Swan is a sludge/doom/stoner metal band from Nottingham, United Kingdom, active since 2013 and delivering crushing, fuzz-laden heaviness where doom's oppressive weight meets stoner metal's hazy grooves. The project channels low-end power and psychedelic atmosphere.

Iron Walrus is a doom/sludge metal band from Osnabruck, Germany, active since 2014, crafting monolithic compositions of crushing heaviness. Over a decade, the band has forged a formidable sound that merges doom's glacial weight with sludge's abrasive filth.

Iron Witch is a sludge/doom metal act from Liverpool, United Kingdom, active since 2011 and channeling monolithic heaviness through its doom metal framework. The project delivers oppressive, glacially paced compositions.

Isaiah is a death metal with black/sludge metal influences act from Northampton, United Kingdom, active since 2019 and merging the atmospheric darkness of black metal with death metal's crushing brutality. The project delivers fierce extremity at the crossroads of both genres.

Metal band from Guadalajara in central Spain, active since 2013, evolving from early sludge/post-metal into heavier stoner metal/rock territory. Their stylistic shift reflects a move toward riff-driven heaviness.