How many Rs are in "Pentagonal Trapezohedron"?

Pentagonal Trapezohedron ⋅ (pen-tag-o-nal trap-ee-zoh-hee-dron) ⋅ noun

A dual polyhedron consisting of 10 congruent kite-shaped faces, known primarily to geometry buffs as the “dual of the pentagonal antiprism” and to everyone else as the “ten-sided die” (d10). It is the only reason your tabletop RPG character knows exactly how much fire damage that dragon just dealt.

So yes, D10. Two pyramids, each 5 kites. Looks like this:

(DISCLAIMER: Generative AI was not used when generating this image (most likely), I found it on good ol internet and pasted it here without attribution like there’s no tomorrow)

So I wanted to have a fun D10 roll experience in a project I scratched after rewriting it 3 times recently and I realized that for some reasons, LLMs struggle a bit with the shape. Not just defining it in 3d, but also doing a projection of that.

Anyway, this is just what state-of-the-art models do for the exact same prompt:

Create a simple web app: an interactive 3d view, where you can roll a D6 dice (…) Now add an option to select a dice: D6 or D10

Gemini (3, thinking)

🏅 For creativity to avoid the shape when knowing its weakness

OpenAI (gipiti 5.4)

🏅 For courage of presenting this fucked up thing

Claude (Opus 4.6)

🏅 For one shotting without errors and confidence in believing how the shape looks like