I could not find any Malefactor out there, as this old epic model never got a port to "recent" 40k by GW or FW. I mixed many parts to bring it to life (exocrine body with part of hyerodule body, top of carnifex head, BFG cruiser front for the mouth, lictor scythe for the arms) and applied some Blender on it to smooth it out somewhat.

2020-06-15: I've updated the model, apparently I did not export my model with "smooth" carapace and had two vestige of vent that I removed still visible, I fixed that.