<p>The Ransko (ultra)mafic massif, Bohemian Massif, Czech Republic, hosts several Ni–Cu–(PGE) deposits and peculiar Zn–Cu–Ba ores. Geochronology integrated with petrography, bulk-rock, and mineral compositions together with Sr–Nd–Pb–Hf–Os–O isotopic systematics of barren and variably mineralized (ultra)mafic lithologies as well as massive ores reveal a complex evolution of the Ransko massif and its mineralizations. The Sm–Nd and U–Pb ages obtained for gabbros and cross-cutting granite porphyry, respectively, overlap with Re–Os ages of Ni–Cu–(PGE) and Zn–Cu ores and limit the formation age of (ultra)mafic rocks and metal accumulations to ~ 370–345&#xa0;Ma. Compositional variations indicate derivation of parental melts of the Ransko massif from metasomatized, Variscan sub-arc mantle and underscore the importance of assimilation–fractional crystallization and crystal accumulation processes. The Ni–Cu ores were emplaced through the gravity-driven percolation of dense sulfide liquids along previously weakened structures associated with the downward crystal fractionation. The orogenic and arc-related nature of the Ransko Ni–Cu–(PGE) mineralization shares some remarkable similarities with some other Ni–Cu deposits in the European Variscan Belt highlighting the significance of these deposits emplaced in arc-related crustal domains. Yet, the variable nature of these mineralizations indicates complex processes that happen during the emplacement and evolution of the parental magmas driving their favourable metal contents.</p>