Triceratops

Common Name: Triceratops
Species: Triceratops styrax
Time: Late Cretaceous
Diet: Herbivore
Temperament: Short-Tempered

Wild:
Apparently a cross-breed of a Triceratops and Styracosaurus, Triceratops styrax has both the characteristic three-horned face of Triceratops and the prominent horned-ridge of Styracosarus.

Normally a very docile grazing animal, Triceratops becomes extremely aggressive once angered. Triceratops will chase down would-be predators (and egg-stealers) with incredible prejudice. I've seen Triceratops have an especially hostile reaction to the Tyrannosaurus on the island, with herds attacking in groups.

Domesticated:
A common mount for those that ride dinosaurs, Triceratops doubles as both pack animal and combat war horse. Triceraptops' bony ridge works excellently as cover from frontal attacks, and the dinosaur's charge is incredibly dangerous.