Though both the goblin nations of Gammon and Catawampus claim to have resident immortal beasts, humans generally consider these creatures to be the stuff of legends, though Vít Karolek, author of Flora, Fauna, and Fungi of the Goblin World, claimed to have personally come across one. His book includes the following passage:
I have chosen to include immortal beasts under “Fauna”, though I do not suppose they are exactly what we would consider animals. Little is known about these rare creatures, though there has been some consensus among goblin scholars. The beasts have a fluid, or potential, form which gives them the ability to change shape. Some legends hold that the beasts can share their thoughts merely by touching another creature, though why they would want to is anyone’s guess. It is also believed that they do not age, nor reproduce. Whether they can be killed by anything is doubtful, and whether or not they can feel pain is up for grabs as well. Information on these creatures is hard to come by, and when found is too vague to matter. It would seem that the beasts want to keep it that way.
There was once a time when stories of such beasts were in vogue in the countries that would one day become the Empire. While some of this materialized in trivialities, such as “the drink of the immortals”—an earthy pu-erh tea said to have been introduced to humanity by an immortal beast—certain intellectuals seriously considered the metaphysics of how such creatures would actually operate. Some theorized that the beasts existed as potential realities, as opposed to the actual existence experienced by most beings (a theory to which Vít Karolek apparently subscribed). This potentiality would allow the beasts their shape-shifting ability, as they temporarily actualized the forms of other creatures. While some theorists insisted that the beasts could literally become anything, including non-living objects, others have concluded that a beast could only shapeshift to look like living creatures, and each beast—having its own unique identity—would only be able to take the form of a particular individual of each species.