Create a 3D model of Mokoi’s ultimate form, a fusion of shadow, primal beast, spirit, and natural elements, emanating an aura of pure malice. The body should combine elements from each of the previous forms—elongated shadow limbs, beast-like muscular build, ghostly features, and nature-based textures like vines and stone. Design it with glowing red eyes and a menacing, ancient presence, as if it rules the mystical realm. Add dark energy flowing around its form, and ensure the textures emphasize its combined power and supernatural origin.