The development of high-performance materials capable of resisting wear under wide temperature ranges remains a challenge. In this work, TiVNiW x (x=1, 0.5, 0.2) compositionally complex alloys (CCAs) were developed via negative mixing enthalpy (∆H mix) compositional design and consolidated by spark plasma sintering (SPS), enabling thermodynamically driven phase separation under rapid non-equilibrium conditions. The alloys exhibit a multiscale heterogeneity (ranging from nanometers to micrometers), including coherent dual BCC phases, Ti-rich HCP regions, η-Ni 3Ti precipitates, and nanoscale precipitates. This cross-scale structure activates synergistic strengthening mechanisms (including solid solution strengthening, precipitation strengthening and hetero-deformation induced hardening), resulting in high macro-hardness (~12.1   GPa). Among them, the TiVNiW 0.5 alloy exhibits superior wear resistance from 25-600℃ due to optimized phase constitution and formation of stable tribo-layers.