The triceratops, a herbivore who lived in the late Cretaceous period, they weighed on average 13,000 – 26,000 lbs. Often times the triceratops would use the horns they had to either compete with other horn dinosaurs for leader or king of the pack. Otherwise the long horn would be used to impale predators such as the Tyrannosaurus rex, Albertosaurus and Spinosaurus, some big meat eaters.