Should probably be printed using 100% infill if you use a cheap PLA. I got some ugly holes in mine because the infill structure collapsed. Print as many copies as you want, but two of each is when the puzzling starts to offer alternative playing fields. Don't try to puzzle the pieces together in the slicer, because that will smear plastic from the other side on the nozzle and create ugly lumps along the surface. There's no overhang in the models, so they are easy to print, but you might need some wood glue and alcohol to easily remove them after printing. Once the print is done, the holes in the pieces will make it easy to pour alcohol from all sides dissolving the glue. After a few minutes, the glue should be fully dissolved any you just nudge the pieces with a blunt tool to remove them. Be careful about flying drops of alcohol that may hurt your eyes. If you want the pieces in different colors and without layer lines, the puzzle has enough gaps between themselves for a thin coat of primer and acrylic car paint. The advantage of acrylic car paint on PLA is that the acetone will smooth the outer layer of plastic without affecting the chemically resistant PLA which holds the correct dimensions and you can throw away the failed prints without using non-degradable plastics in the early process. Printing a puzzle in ABS and acetone smoothing would shrink it into a thick wrinkly lump before it's nearly as smooth as acrylic car paint. Play with regular marbles to reduce the use of plastic filament. It's super cheap to buy preowned marbles online if you don't have any.