Disclaimer: the above image is of a concept that does not exist…yet.
Nevertheless, there have been multiple instances in which myth and folklore have been used in popular fiction. One example is Stan Lee’s concept of Thor, who of course is a god with a hammer wielding the fury of the heavens (lightning) whose father is Odin and lives in Asgard.
This is almost exactly the image of Thor from Norse mythology. Stan Lee didn’t change very much, if explicitly anything at all. He only lent his viewpoint and spun some of the details his own way. He borrowed (or should I say, stole) things from other realms to complete his idea.
This isn’t the only case. This can run from Percy Jackson to Narnia to others (to say nothing of how many Robin Hood remakes are out there), each taking elements from old tales (some true, some myth) to make a modern story. Like they say: don’t reinvent the wheel. There’s no shame in taking a good idea that is no longer used.
Now, before you immerse yourself in nerdy lore…know that that was what I was just about to recommend. But listen a moment longer: yes, it’s a good idea to go off to the Wikipedia and read everything you can about obscure characters from mythology, but there’s one more thing you have to spot: the concept.
You see, getting the knack of this technique is more than just a simple “oh, I can just copy the whole thing”. That’s not how it works, and this even applies to larger parts of lore: don’t just copy and paste large segments of old stories into your work. The idea is to grasp the concept.
The concept is going to be much smaller than plot or characters. The goal is to take certain things about those plots and characters and use them with enough original thinking on our side. Things about the plot and characters are different from the plot and characters themselves.
Practice looking at the small details. For example: I read Greek mythology and see that the God Hermes has winged sandals, a magic cloak, and a magic wand, as well as a feathered cap. What if I want to incorporate this into my sci-fi story? Well, take a few aspects: let’s say, the winged sandals, the magic cloak, and the name.
Those are qualities that Hermes possesses, not who Hermes is. However, your goal wasn’t to rewrite a Greek myth with minor changes, you want to write your own story. So I take the said elements of Hermes, and I introduce the reader to a laser-gun-wielding masked rocket-booted (how winged sandals transmute into sci-fi), heavily cloaked (hides his body, also a reference to the cape) revolutionary named Hermes. For an added bonus, I’ll just throw in that he ferries messages for the Interplanetary *blank* Guild (Hermes was the official messenger of the gods).
A judicious reader might see the connections, but I doubt that they will not appreciate your choice. I doubt they’d be like, “This is the cheapest piece of crap I’ve ever read. This is blatantly (subtly, actually) a mooch off the Greek myths. What a rip-off.” I don’t think that this will be your fate if you so choose to do this.
The myths of old possess a lot of material to work with. They’re useful for more than just campfire stories: the characters, plot, and concepts are folk-generated and carefully crafted. It’s like the difference between an artisan hand-made sword and a mass-produced one.
Good luck, and happy writing!
The Writer's Rack 