Monolophosaurus was a mid sized theropod that was about 5–6 meters in length, and weighing up to 1,500 pounds. This predator is most famous by its head crest, though it is more advanced then the primitive crested dinosaurs like Dilophosaurus. It was known to hunt in packs to bring downs sauropods like the more advanced carnivores during the later times of the Jurassic. It had lots of sharp, serrated teeth and a big, skinny head. The area that Monolophosaurus was found showed signs of water, so it is possible that this dinosaur probably lived on the shore of lakes and oceans.