Inspired by a dragon's egg.. or what they could look like if you imagined one ;-) Design intended for dualstrusion, but monostruders, do not despair:
You can print "Net" or "Surface" as standalones. Circa 11 cm high, scale as needed. So there are two different models:
One where the pattern is embedded near the surface. (Left)
And one where the pattern is completely embedded in the shell. (Right) Suitable for dual extrusion printers.
There are four files of which you only need two in one print:
Always use the "Net" stl and combine with either a one "Surface" OR "Embedded" stl
Please look at the split render to see the full difference.
There is a thin and a thicker version of the Surface shell, choose which one your printer can handle.
The 2mm is also a nice standalone print.