Emerging engine hot-section components are focused on SiCf/SiC composite with environmental barrier coating (EBC) that can withstand harsh thermal and chemical attacks against combustion environment. Typical EBCs provide reliable protections to SiCf/SiC components below the surface temperature of 1300?. However, the present EBCs demonstrate limited capability of corrosion resistances to hot steam and molten CaO-MgO-Al2O3-SiO2 (CMAS) deposit at higher temperatures, as well as the phase instability and amorphization during coating fabrication. To address these critical challenges, new strategies are adopted to design new rare-earth silicate EBCs through multilevel optimizations, including both the multi-RE-component (or high entropy) modification and microstructure regulation. The advancement of new multi-RE-component silicate EBCs may support the requirements of future SiCf/SiC composite engine components.