A Sea Serpent is a reptile living underwater. They come in many sizes, from the size of a firefly to almost as big as a legendary dragon. The bigger ones sometimes attack ships. All Sea Serpents are either carnivores/piscivores or scavengers, depending on the size (the bigger the size, the more likely it is to be a carnivore/piscivore). They are born small and eventually grow to monstrous sizes if left alone, so even tiny parents can produce offspring that will grow to a large size. It is believed that they never stop growing. They breathe using lungs, and their throat can filter oxygen from hydrogen when underwater. In the past, it was thought that the Water Dragon was a type of Sea Serpent.
Sea Serpents are distinguished from dragons by their lack of any magic.