Dracorex is a inosaur genus of the family Pachycephalosauridae, from the Late Cretaceous of North America. The type (and only) species is Dracorex hogwartsia, meaning "dragon king of Hogwarts". It is known from one nearly complete skull (the holotype TCMI 2004.17.1), as well as four cervical vertebrae including the atlas, third, ninth and eighth. These were discovered in the Hell Creek Formation in South Dakota by three amateur paleontologists from Sioux City, Iowa. The skull was subsequently donated to the Children's Museum of Indianapolis for study in 2004, and was formally described by Bob Bakker and Robert Sullivan in 2006. A second slightly distorted skull has subsequently been discovered in a different locality.