WWD: Dakotaraptor steini (Patreon)

Here we get into taxa which were not known to have existed at the time of original production, the unnamed dromaeosaur of the episode (a palette swap of the Utahraptor, itself an enlarged Deinonychus), which was identified in supplementary media as Dromaeosaurus. It was probably not called that by name in the episode because Dromaeosaurus is not definitively known from the Late Maastrichtian, it's only known for certain from Campanian deposits, although teeth tentatively assigned to the genus are known from the Maastrichtian. Since the episode, two dromaeosaur species have been identified from Hell Creek, the coyote-sized Acheroraptor and the tiger-sized Dakotaraptor. Teeth tentatively assigned to Dromaeosaurus from Hell Creek are now believed to most likely belong to Acheroraptor.

Given the series' tendency to pick bigger and more spectacular animals, I have no doubt they would have chosen Dakotaraptor over Acheroraptor had the options been known back then (and the idea of two tiger-sized dromaeosaurs threatening elephant-sized Torosaurus being more believable than two coyote-sized ones). This was one of the largest known dromaeosaurs and the second-largest dinosaur predator from Hell Creek (of course the gap between first and second is huge). There is some controversy regarding Dakotaraptor regarding its describer and its possible status as a chimera, but I won't get into it here, and, as far as I know, there's nobody saying there wasn't a giant dromaeosaur from Hell Creek.