Magnesium matrix surface composites have been garnering attention due to their superior mechanical and corrosion resistance properties. An idea of facile fabrication of surface composite composed of nano-SiC reinforced WE43 matrix through friction stir processing was explored in this study. Also, the effects of tool geometries, tool rotations, and tool feeds on physicochemical, metallurgical, and mechanical properties were comprehensively investigated. Following characterization using XRD, FESEM, EDX, and OM tools, substrates were also tested for their microhardness, nanohardness, elasticity, and wear resistance properties. Uniform dispersion of SiC nanoparticles within the stir zone was evident. The square tool demonstrated the most promising results. Processing at 1700 rev/min and 60 mm/min with a square tool produced the finest grains in surface composites that exhibited exceptional microhardness (180.8 HV), nanohardness (1.867 GPa), elastic modulus (41.69 GPa), and wear resistance (0.0254 mm3/min). Besides it, WE43 substrates also exhibited superior mechanical properties when processed with a square tool at 800 rev/min and 60 mm/min. This research opens up new possibilities for the development of reliable magnesium matrix surface composites for multifunctional applications.