The program received some criticism due to Horner's negligence to take note of any evidence that might confirm the opposite of his theories.
The work provides examples of:
- Artistic License Biology:
- Horner compares T. rex to spotted hyenas for his argument, because everyone knows spotted hyenas are disgusting, cowardly scavengers.
- Small arms make hunting difficult? Wolves, crocodiles, and sharks would like a word with you, Mr. Horner.
- Artistic License Paleontology:
- The program was well constructed and explained in detail why it presented the things the way it has, but paleontologists that happened not to hate Tyrannosaurus *Cough*Robert Bakker*Cough* may find it to be somewhat infuriating.
- That having been said, not all of Horner's facts make sense. Could an animal that size support itself by being lucky enough to constantly bump into still-edible dinosaur carcasses whenever it was hungry?
- Horner suggested dromaeosaurs would be the true top predators instead of T. rex, and the documentary proceeds to show them bringing down prey many times their size in numbers. This is, of course, analogous to jackals bringing down an elephant. Though this was before the discovery of Dakotaraptor....
- False Dichotomy: Pure hunter or pure scavenger? Why can't T. rex be a bit of both?
- Feathered Fiend: Saurornitholestes and a bunch of other small dromaeosaurs which the rex chases away from their kill.
- Raptor Attack: The Saurornitholestes are not only inaccurately feathered, they were also shown bringing down an Edmontosaurus many times their size and have also managed to kill a Triceratops, against all logic.
- Scavengers Are Scum: The scavenging T. rex as imagined by Horner is depicted in an extremely negative light, in contrast to the nobler image of the classic predatory version.
- Science Marches On: With more and more evidence arising to support the "predator" theory, even Horner himself admitted he was wrong about the animal.
- Stock Footage: From Discovery's former dinosaur show, When Dinosaurs Roamed America.
- Stock Sound Effects: The roars uttered by the T.rex when it scares away a few smaller theropods from their kill are very obviously modified grizzly bear roars.
- The Makeover: Inverted. Horner takes a standard CGI Tyrannosaurus and turns it disgustingly ugly — or, in his mind, more realistic.
- The Worf Effect: A meta-example. What has previously been seen as the ultimate predator is actually a pathetic carrion stealer. At least, that was what the documentary set out to accomplish.
- Tyrannosaurus rex