It looks like an alien creature that feeds on the flesh and blood of fish or marine mammals, so-called "water vampires". In fact, the real cause of death of ferrante I was colorectal cancer, which had nothing to do with the lamprey, but the reason why the screenwriter's brain was wide open was because there was indeed a king who died because of the lamprey in history. This king is Henry I of England (about 1068- 165438). In the Middle Ages, fishermen were catching lampreys and how to eat them.
They are soaked in wine, because wine is considered to be warm and dry, and then cooked by baking, which is fragrant and tonic. Therefore, even killing a king can't stop the British royal family from pursuing the lamprey. Every Christmas, Charles III (1452- 1485) goes to Gloucester, on the Seine River, to taste the local special food, the lamprey pie. The lamprey is only a small part of the dark European cuisine in the Middle Ages, and this menu even includes "chop sparrows, roast swans, roast antelopes, stew dog meat, cook sea eels, cook dolphins ..."
Many recipes handed down from the Middle Ages are the best evidence: Maino de Maineri, a Milan doctor in the 0/4th century A.D./Kloc, wrote a healthy diet, which recorded dolphin meat. Dolphins are classified as "animal" fish. They are cold and wet, similar to lamprey, and very dangerous, so it is necessary to add a particularly spicy sauce to flavor them when cooking.