Multistable oloid paired half shell sampling.

thingiverse

The sphericon and oloid shapes make a complete contact with their entire surface against a plane during one rolling cycle. These variants are designed for multiple stable positions and can be used as game dice if the faces are labeled and probabilities of face resting are considered. I've created half-shells in ABS that print well, I recommend two perimeter walls, no bottom layer and three top layers, with no infill. The 5-lobed variant fits only one way, for every variant, assembling them correctly involves crossing the hard curved edge on top with the one at the bottom relative to each other, pressing together, then gluing using acetone or a mixture of acetone and ABS glue.