Thirdmoon formed in Linz, Austria in 1994, founded by Wolfgang Rothbauer and initially working in fast-paced melodic black metal before migrating toward melodic death metal over successive releases. Their debut Grotesque Autumnal Weepings (1997) established their sound, followed by Aquis Submersus (1999) and Bloodforsaken (2000) on Napalm Records, which shifted the band's approach toward heavier melodic death territory. After parting from Napalm, further albums appeared over subsequent years including Sworn Enemy: Heaven and Terrarum Exuviae (2018), marking a long-running career that spans multiple stylistic phases within the extreme metal spectrum.

Thirst Prayer from Milan blend black metal with grindcore's brevity since 2017. Their compositions channel desperate, parched invocation through the Italian fashion capital's extreme underground.

Thirty Aethyrs from Manchester craft progressive and black metal named after the thirty ethereal realms of Enochian mysticism since 2011. Over a decade of esoteric compositions from the northwest has explored each mystical plane through technically ambitious extremity.

THIS GIFT IS A CURSE formed in Stockholm, Sweden in 2008, founded by vocalist Jonas A. Holmberg and drummer Johan Nordlund, with their debut EP recorded at the legendary Sunlight Studios with producer Tomas Skogsberg in 2010. The band works in a cataclysmic fusion of black metal, sludge, and hardcore, constructing songs that balance ferocity with a suffocating, doom-laden atmosphere. Full-lengths I, Guilt Bearer (2012), All Hail the Swinelord (2015), A Throne of Ash (2019), and Heir (2025, released on Season of Mist) have steadily built their standing in the European extreme underground.

This Is Past is a psychedelic black metal band from Athens, active since 1999. With over two decades of exploring the intersection of psychedelia and black metal, they are among the more veteran experimentalists in the Greek underground.

Thlimmos is an avant-garde black metal project from Greece, formed in 2020. Their Greek name, meaning 'sorrow' or 'affliction,' permeates their experimental approach to black metal.

Thod from Paris craft blackened doom metal whose name evokes ancient, ominous weight since 2023. Their compositions merge black metal's atmospheric hostility with doom's crushing pace from the French capital.

Thore is a black/Viking metal band from Bavaria, Germany, formed in 2015. They fuse Norse-themed Viking metal with black metal's cold aggression.

Thormesis is a pagan/black metal band from Rothenburg ob der Tauber, Germany, formed in 2015. They channel Germanic pagan traditions through raw black metal from the medieval Franconian town.