My sister, ChaosCoyote, asked me to print her some 12-sided d4s. She found an STL for one, and I printed a few. They were tiny and I didn't like them. So, I scaled them up, and tried letting Lychee support them.
DON'T DO THAT.
UVTools had an aneurism and warned against the supporting. So, I did some research and
supported them manually.
They
came out great.
It's a pain, but, the nutshell is: put a point down, not a flat side. Support the edges
aggressively. If you think you should put more supports in,
do it. Try to keep the supports off the face, and keep them on corners/edges.