Tyrannosaurus rex, the famous king of dinosaurs, was a top predator of its day.Well-armed with terrifying jaws, it was seemingly impervious to attack.But new fossils are revealing that the life of T. rex and its cousins was brutal.Fossils are probed with cutting-edge techniques to reveal the source of injuries, predation attempts that went wrong and titanic battles where T. rex teeth were sunk into their adversaries.