This video uncovers the incredible defenses that made Triceratops one of the toughest dinosaurs to ever roam Earth. Viewers learn how its horns, frill, and body mass turned it into a living shield.

It's known as the "Dueling Dinosaurs" fossil: A triceratops and a tyrannosaur, skeletons entangled, locked in apparent combat right up until the moment of their mutual demise. Even in the Hell Creek ...