Styracosaurus

Surprisingly, the CollectA Styracosaurus is bigger and more accurate than the costlier Schleich replica. It is more suitable as an illustration for a post on the taxon.
Styracosaurus albertensis lived in what is now western Canada. Its remains occur in the middle of the Dinosaur Park formation, deposited about 75 million years ago. This horizon also yielded evidence of a huge tyrannosaur. Phil Currie found a fragment of one bigger than Daspletosaurus torosus.  At the time, sea levels were low by Campanian standards, enabling dinosaurs to become larger and more formidable.
Well-armed herbivores like Styracosaurus mirrored the tyrannosaurid threat. Unlike the later centrosaurines Achelousaurus and Pachyrhinosaurus, Styracosaurus had a prominent nasal horn. Like a rhino, it charged and impaled its enemies. Stabbing the belly of a tyrannosaur could easily prove fatal. The frill spikes of Styracosarus also played a role in defense.
In part, the spikes evolved for display and to intimidate rivals of its own species. But they also made Styracosaurus appear too dangerous to some tyrannosaurs, and hindered attacks on the neck and shoulders if the horn missed the mark.
The period of Campanian escalation did not last long. But it produced some of the deadliest defenders of the Mesozoic.