Xiphactinus was one of the largest bony fish ever to swim the seas, prowling the warm waters of the Late Cretaceous around 85 million years ago. Its fossils are famous across North America, from the chalk beds of Kansas to Canada, where entire skeletons are sometimes found with their last meal still inside them. Xiphactinus was a sleek, powerful predator that could grow over 5 meters long, with a mouth full of sharp, needle-like teeth and a massive lower jaw that gave it a fearsome, bulldog-like bite. It hunted smaller fish relentlessly, and fossilized specimens have even been found with a smaller Xiphactinus swallowed whole. Fast, aggressive, and built like a torpedo, it was one of the top hunters of the ancient inland seas.