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English: Siats is a controversial large theropod from the Late Cretaceous of North America, named after a man-eating monster of Ute mythology. Thanks to the uncertain nature of its fossil remains, it has been classified as a megaraptoran, allosauroid, and tyrannosaurid at various stages of research. Siats as an allosauroid would show that this group survived all the way to the Late Cretaceous before ceding to tyrannosaurs as the apex predators of North America. At 12 m in length and 4 t in body mass, it would certainly be the top predator in its habitat. But until further fossil evidence is discovered, the debate goes on regarding its phylogenetic affinities.