Great pyramidic swirlprism

The great pyramidic swirlprism or gypasp is a nonconvex noble scaliform polychoron. It consists of 240 pentagrammic pyramids in 120 coplanar pairs.

It can be formed by blending a great swirlprism with a great faceted hexacosichoron.

Its vertex figure is the dual of the vertex figure of sisp.