Stygimoloch is smaller than the Pachycephalosaurus, but is more robust with a
very thick neck. The head is really big compared to the body size, the spikes
are slightly different in arrangement, has a goat-like pupil which is unlikely,
the torso is too short, has a much larger dome on its head, the tail is too
flexible, and has pronated wrists with claws on all five digits. The coloring is
mostly reddish, with an creamy underbelly, some black lightning marks on its
back and head, a white dome, dark grey spikes, a dark grey streak around its
dome, dark grey and dark brown patterning all over the body.