Sludge/stoner metal band from Ostrów Wielkopolski, Poland, active since 2012. Their nature-themed name accompanies heavy, riff-driven stoner sludge from the Greater Poland region.

Rorcal is a Geneva-based extreme metal band formed in 2007, blending doom, black metal, drone, and post-hardcore into a crushing, genre-defying sound. Signed to Hummus Records and supported by the City of Geneva and ProHelvetia (Swiss Arts Council), their discography includes Silence, Witch Coven, and Muladona.

Rosy Finch is a sludge/stoner metal and noise rock band from Alicante on the Costa Blanca of Spain, active since 2013. The band blends heavy sludge and stoner metal with noise rock dissonance from the Levantine coast.

Doom/sludge metal/crust band from Vladivostok in Russia's Far East, formed in 2019. Their triple-genre approach delivers crushing heaviness from the Pacific coast city.

Sludge/death metal/grindcore band from Worcester, England, with roots dating to 2005. Two decades of triple-genre extreme metal from the West Midlands represent exceptional underground longevity.

Rowan is a doom and sludge metal project from Minsk, Belarus, formed in 2019 and operating in the slow, heavy tradition of the genre. The project contributes to the surprisingly active Belarusian heavy underground scene that has produced numerous sludge and doom acts.

Rutsa is a sludge metal and grindcore band from the Kitee/Joensuu area in eastern Finland, active since 2016. The band merges the crushing weight of sludge with grindcore's blast-beat intensity from North Karelia.