Using Substance Painter I could easily gauge the look of the mossy areas, before scattering Megascans moss on top with XGen.
Base Mesh with Displacement & Normal Maps.
highres sculpt for comparison with below. Note the sharp edges get lost e.g. the damaged corner
3 subdivisions with autobump seems to be sweet spot. But still not happy with the overall softening & bloating.
Testing different subdivision settings for the displacement map.
Sculpt vs base mesh.
Damage pass in Zbrush - mostly alphas, trimed edges and a bit of NoiseMaker.
Rather than trying to model the legs in maya, I just used booleans in Zbrush with simple shapes and zremeshed the result.