Small dispinosnub prismatodisnub pentishexacosichoron

The small dispinosnub prismatodisnub pentishexacosichoron, or sidnaspidspox, is a nonconvex uniform polychoron that consists of 600 great dodecahedra and 600 icosahedra (some of which lie in the same hyperplanes, forming 600 compounds of one of each), 4800 cubohemioctahedra (forming 2400 compounds of two), 600 truncated icosahedra, 600 small rhombidodecahedra, 600 small dodecicosahedra, and 6000 triangular prisms.

One great dodecahedron and one icosahedron (two compounds), eight cubohemioctahedra (eight compounds), five truncated icosahedra, five small rhombidodecahedra, five small dodecicosahedra, and five triangular prisms join at each vertex.

It can be obtained as the blend of 5 small spinobased dipentary hexacositrishecatonicosachora and 5 small dipentary hecatonicosiprismatohexacosihecatonicosachora. 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.