This is the main skull on the Destiny Hunter Extoic Arms piece, Young Ahamkara's Spine. This was my first time ever doing any 3D modeling, so it might not be the best! I took the file from DestinySTLGenerator, hollowed it out, smoothed it, and added a lot of the detail back into it.
UPDATE Feb 2021: 5 years later, finally posted pictures of how I finished this piece after I printed it.
1: Filler primer and spot putty, lots of sanding.
2: Added crafting putty and then sculped with an x-acto to get the look of the gums and added bone structure and "organic" details that either wouldn't show if printed and/or I couldn't get to turn out right in the cadding software (my lack of cadding/design skill...)
4: Airbrushing and painting
5: (no pictures) hand made the leather straps out of crafting leather with eyelets, etc. Elastic straps to go around the arm, and a strap with a snap-button that would attach to the armor chest piece to hold the head on her shoulder.
The spine and jaw pieces were printed straight as they come off the STL Generator site, in really low poly. I just covered them in bondo, lots of sanding and painting, mounted to leather, added straps.
I printed it as it imports (verticle) and with supports EVERYWHERE (not just Touching Buildplate!) for all angles over 45*. You can probably print it flat as well and/or possibly with a steeper angle requirement. Just check for all the supports in the layers, there's a lot of weird overhangs around the nose area!
At 0.15mm layer heigh and 20% infill it took about 12 hours to print.