Recreate a mystical age when dinosaurs roamed the earth! Tyrannosaurus, or T-Rex, was a huge, meat-eating dinosaur. It lived during the Late Cretaceous period, about 85 million to 65 million years ago. It's name means "Tyrant Lizard King" and it walked on two legs! The original Tyrannosaurus grew to about 12 metres in length and stood about 6 metres tall... this baby T-Rex is a wee bit smaller than that!