WWD: Acheroraptor temertyorum (Patreon)

This is a replacement of Dakotaraptor since new information (informally) has come to light suggesting the animal may not actually exist. It seems likely that it is in actuality a mixture of bones from various different animals rather than a true taxon (it was already established its supposed bones came from a multi-species jumble that likely constituted a riverbed location at the time). This is on top of the original descriptor being of dubious merits (although I won't get into detail on that here).

It had been established that the supposed wishbone was actually a fragment of a softshell turtle carpace (specifically Axestemys), but it also seems the tail bones more likely came from an ornithomimid, the leg bones from a large oviraptorosaur (probably Anzu), and the claws, and possibly teeth, likely originating from a juvenile Tyrannosaurus. Only a single tail vertebrae seems to be definitively dromaeosaur, but this belongs to a roughly Deinonychus-sized animal, not the Utahraptor/Achillobator-scale animal that Dakotaraptor was suggested as. 

Therefore the only dromaeosaur taxon definitely known from Hell Creek is Acheroraptor (teeth from the site identified as Dromaeosaurus sp. also likely belong to Acheroraptor), and it's possible this vertebrae actually belongs to Acheroraptor. Although it's larger than other dromaeosaur remains known from the formation, the holotype of Acheroraptor represents an immature animal, making it totally possible that the adult could've gotten to such a size, so here's it's illustrated as being larger than the definitive Acheroraptor is thought to be (lack of overlapping remains makes it impossible to currently confirm this idea however).