Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:5584686.

Box in the shape of a skull in two parts that fit together.

With wall thicknesses of 1.2mm and a tolerance (space for interlocking) of 0.4mm.

Each part, prints, the side with the largest flat surface on the print bed. ( does not require any supports. )

In the event of a print bed adhesion problem, use a brim.

If you have any questions or criticisms, or if you want another version (dimensions, or wall thickness, or nesting tolerance), please leave a comment.

Happy printing.