Small dispinosnub prismatosnub pentishexacosihexacosichoron

The small dispinosnub prismatosnub pentishexacosihexacosichoron, or sednaspospexox, is a nonconvex uniform polychoron that consists of 600 small stellated dodecahedra and 600 great icosahedra (some of which lie in the same hyperplanes, forming 600 compounds of one of each), 600 great dodecahedra, 4800 cubohemioctahedra (forming 2400 compounds of two), 1200 small dodecicosahedra (forming 600 compounds of two), 600 small rhombicosidodecahedra, and 3600 pentagrammic prisms.

One small stellated dodecahedron and one great icosahedron (two compounds), one great dodecahedron, eight cubohemioctahedra (eight compounds), ten small dodecicosahedra (ten compounds), five small rhombicosidodecahedra, and five pentagrammic prisms join at each vertex.

It can be obtained as the blend of 5 small dipentary hecatonicosiprismatohecatonicosihexacosichora and 5 small dipentary hexacosihecatonicositrishecatonicosachora. 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.