Toltec style includes the presence of the feathered or plumed serpent, called Kukulcan or Quetzalcoatl, chacmools, the Tzompantli skull rack, and Toltec warriors. They are probably the impetus for the increase of emphasis on death culture at Chichén Itzá and elsewhere, including the frequency of human sacrifice and warfare. Architecturally, the elements of colonnades and columned halls with wall benches; pyramids are built of stacked platforms of decreasing size in the "tablud and tablero" style which developed at Teotihuacan. Tablud and tablero refers to the angled stair-step profile of the stacked platform pyramid, seen here in this profile shot of el Castillo.
El Castillo is also an astronomical observatory; on the summer solstice, the stair step profile lights up, the combination of light and shadow make it appear as if a giant snake is slithering down the steps of the pyramid. Mayanist Falken Forshaw reports: "The relationship between Tula and Chichen Itza is debated at length in the new book called A Tale of Two Cities. Recent scholarship (Eric Boot summarizes this in his recent dissertation) indicates that there was never a shared power between peoples, nor shared between "brothers" or co-rulers. There was always a paramount ruler. The Maya did have colonies throughout Mesoamerican, and the one at Teotihuacan is well-known."