This is the Oni Skull from Jooxoe3i, it's so creepy cool! We brought the STL into Autodesk MeshMixer and applied a shell to save on material and printing time. It was printed with a low infill at 100 microns on the Ultimaker 2, with max size. Check out the overhangs, we added custom supports using Simplify3D. Took 12+ hours to print.