Phase prediction in multicomponent alloys remains one of the most fundamental challenges. Navigating the vast compositional space of these alloys requires a predictive capability to efficiently guide alloy discovery and microstructure design. Recently, Dr. Ghazisaeidi has developed a Multicell Monte Carlo (MC)^2 method, based on first-principles calculations, to study phase formation in multicomponent alloys. This method is particularly powerful when applied to multicomponent systems, for which phase diagrams do not exist. First, she introduce the (MC)^2 method and present its successful prediction of the stable phases of known binary systems. Next, she will present the application of (MC)^2 to “high entropy” alloys and discuss the effect of emerging stable phases on deformation mechanisms and consequently the overall mechanical behavior.