Great retroinverted dodecahedronary prismatohecatonicosachoron

The great retroinverted dodecahedronary prismatohecatonicosachoron, or gridaphi, is a nonconvex uniform polychoron that consists of 120 icosahedra and 1200 triangular prisms. Twelve icosahedra and sixty triangular prisms join at each vertex.

It also has great icosahedra and tetrahedra as pseudofacets.

Vertex coordinates
Its vertices are the same as those of its regiment colonel, the small ditrigonary hexacosihecatonicosachoron.