Progressive death/black/sludge metal band from Pomerania, Poland, formed in 2024. Their ambitious four-genre approach pushes extreme metal into progressive territory from the Baltic coast.

Rebuig is a sludge/doom metal band from Barcelona, Spain, formed in 2015. Named after the Catalan word for 'rejection,' the band delivers crushing sludge and doom from the Catalan capital.

Red Apollo is an atmospheric sludge and post-metal band from Dortmund, Germany, active since 2011 and released through Moment of Collapse Records. Their catalog spanning from 2012's Marche Funèbre through 2018's The Laurels of Serenity delivers dense layers of sludge, post-hardcore, and atmospheric black metal influences.

Red Mourning is a stoner/sludge metal band from Paris, France, active since 2008. Over a decade of sludge-drenched heaviness from the French capital establishes them in the Parisian doom underground.

Red Sativa is a sludge/doom metal band from Marseille on the Mediterranean coast of France, formed in 2018. The band delivers crushing sludge and doom from the port city of Provence.

Sludge/stoner metal band from Budapest, Hungary, active since 2016. Their swamp-themed name accompanies corrosive, heavy riff worship from the Hungarian capital.

Sludge/post-metal band from the Porto/São João da Madeira area, Portugal, active since 2015. Their approach blends sludge metal's crushing heaviness with post-metal's atmospheric expansiveness.

Redjeven is a doom/sludge metal and ambient studio project from Hildesheim in Lower Saxony, Germany, formed in 2020 by musicians Waldseel and Niese. Their 2020 debut Pulsschlag der Elemente combines distorted doom and drone metal with industrial and grind influences, featuring cover artwork containing approximately 2,600 illustrated heads created by artist Tilo Eichhoff.

Redwood Hill is a five-piece post-black metal and sludge band from Copenhagen, Denmark, formed in 2013, drawing from 'a cold and depressive aesthetic expression with a lyrical universe revolving around the dark corners of the human mind.' Their extensive catalog from 2013's Descender through 2025's Ammonia balances powerful highs with enigmatic, haunting lows.