All of the Platonic Pairs
Platonic solids are extremely unique mathematical shapes that all share properties of perfect symmetry of each face and vertex. There are only 5 platonic solids, the tetrahedron, cube, octahedron, dodecahedron and the icosahedron. These shapes can be paired up so every single vertex of one solid matches up with the center of the face of another. The platonic pairs are: the dodecahedron-icosahedron pair, and the octahedron-cube pair. Tetrahedron is unique because it is its own pair. They are appear deceptively simple, yet these shapes require high technical precision and intense usage of 3D sketching. Their mathematical definitions are often irritating to execute, especially the dodecahedron. Their complexity comes from the number of verticies and edges each of them feature. This also causes extreme difficulty for software rendering.