Herein, a novel refractory Nb30Mo30Ti20Co20 (at. %) high-entropy superalloy (RHESA) is introduced. Annealing at 1200 °C led to the precipitation of semi-coherent individual (Co, Ti)-rich B2, (Ti, O)-rich fcc (Ti-rich oxides), and hierarchical B2 + nanoparticles in (Nb, Mo)-rich RHESA bcc phase. dispersoids were dominant, they nucleated heterogeneously because coherency ensured by Baker–Nutting ...