Very high flexibility, articulated model of the Reaper bones that can be found in the Lost River.The body parts snap into each other.The jaw hinges. The fin bones slide into the 4th rib from the neck and stay in place using friction.

3D printing settings

Only support the head.The backbones are optional, if you choose to print them, they're made to slide in the back holes using friction, but this might depend on your filament/printer tolerances.If you find that your filament is over-extruding, size down the backbones a few percent.If it's too loose, either size it up or super-glue them. Enable Brim to keep them in place when printing.