Small dispinosnub prismatosnub heptishexacosichoron

The small dispinosnub prismatosnub heptishexacosichoron, or sednasposhex, is a nonconvex uniform polychoron that consists of 1200 small stellated dodecahedra (some of which lie in the same hyperplanes, forming 600 pentagrammatic snub pseudodisoctahedra), 1200 great dodecahedra (forming 600 pentagonal retrosnub pseudodisoctahedra), 4800 cubohemioctahedra (forming 2400 compounds of two), 600 rhombidodecadodecahedra, 600 small dodecicosahedra, 600 truncated icosahedra, and 3600 pentagrammic prisms.

Two small stellated dodecahedra (two compounds), two great dodecahedra (two compounds), eight cubohemioctahedra (eight compounds), five rhombidodecadodecahedra, five small dodecicosahedra, five truncated icosahedra, and five pentagrammic prisms join at each vertex.

It can be obtained as the blend of 5 small capped dipentary tetrishecatonicosihexacosichora and 5 small capped dipentary prismatohexacositrishecatonicosachora. In the process, some of the cubohemioctahedron cells blend out.

Vertex coordinates
Its vertices are the same as those of its regiment colonel, the small diretrosnub disnub decahecatonicosadishexacosichoron.