Figures of Note
Earth mythologies are full of interesting characters that are not gods or humans. This includes Charon, who ferries souls across the rivers Styx and Acheron. There’s Cerberus, the three-headed dog in Greek mythology, who prevents the dead from leaving Hades. For ideas, all we need to do is look at other mythologies. We may want to start with a role or job function, which will also give us a location this individual occupies, and its characteristics. If the River Styx has properties we’ve already invented, and effects on people, then our version of Charon might be able to control or counteract these for at least himself.
The gods are often the source of such figures, who arguably need their approval to perform the function they serve. But these figures can come from any source, such as supernatural accidents before they are put to the use they now serve. A god may be the only one who can control it, possibly using a device that can fall into the wrong hands. Other times, an individual from a species or race might have been transformed into this figure, possibly due to their devotion to an idea that the god agrees with. For example, Charon could believe that everyone must be judged upon death and was so fervent about this in life that Hades assigned him to transporting souls. This gives such a character an attitude that can be revealed while interacting with our characters.
We may not think of cartoon characters like Spiderman or the X-men as supernatural beings, but they’re close. Most of us would agree that they have supernatural abilities though not intrinsically supernatural. There are few limits on using these elements to transform them if it’s credible. What happened to them, when, why, and how did it affect them physically? Decide how much control they have over their skills at the point of the story that they’ll be used. Like any character, they need backstory, just one with extra information.
Another supernatural being is the “familiar” of wizardry. They originate in medieval folklore and were though to assist witches, or perhaps in our case, wizards, including protecting them, whether that means physically or scouting and warning. They may also possess specialized knowledge, particularly of a plane of existence different from which they originate. They are usually in the form of a small animal and appear corporeal rather than ghostly, though we’re free to do either. We can make them invisible to others, too. Whether they’re considered good or evil depends on who they serve; they might be considered fairies or demons. Familiars are sometimes given as a gift, or appear when someone is alone or in trouble, after which they are bonded from weeks to decades.