The term 'mythical sea monsters' can refer to a variety of creatures from different cultures. One example is orcs, which are found in the works of J.R.R. Tolkien and other fantasy authors. They are typically described as large, brutish humanoids with green skin and tusks. In some stories, they are portrayed as evil creatures that inhabit the sea and attack ships. In other stories, they are depicted as more benevolent creatures that help sailors in distress.