This is an easy-to-print multicolor chonk D20 for FDM printers.

Print the panels face down to capture the bed texture and make it feel less “printed”, use a bit of glue to fix the panels in place.
I've designed in some tolerances to make them easy to assemble though it depends a lot on your printer and how well your profile handles accurate dimensions. You can lightly sand the edges of the panels if its too tight, or simply scale them slightly in your slicer.