Long time no write! I'm sorry it's taken so long for me to get back to the blog, but I'm hoping to post regularly now that I'm leading a Fantasy/Sci-Fi group in Iowa City. I'll post more information about that later. For now, I would like to talk about the art of creating a God system. Many fantasy/sci-fi stories present different forms of higher powers. But how do you make them? It's really up to you, but I can give you some ideas on how to get started based on what I've done in my own writing and what I've seen.
Gods based on mythology
One way to introduce Gods into your book is to look into mythology. For example, what Gods appear in Norse mythology, Greek mythology, Celtic mythology, etc.? Each one of these Gods has a purpose, an appearance, a reason to be in the story. If you're rewriting mythology, you can freely use these Gods to your own desire. Maybe Thor makes an appearance, or Odin, or Apollo and Athena. Perhaps you're writing about vikings and you want to keep true to Norse mythology.
My advice to you is if you're stumped, read different types of mythology and see if you can create Gods that way, or reinvent those Gods. It's okay to take something that's already known and apply it to your writing, just try to put an interesting twist to it!
Symbolic Gods
My favorite thing to do is to create Gods based on symbols or elements. For example, I have five Gods in one book. Each one is based on the seasons: Fall, Winter, Summer, Spring. The final God, however, is the Goddess of balance, neither light nor dark, life nor death. Each God represents a compass location, have particular colors, and are said to provide particular gifts to mortals.
One example is my Goddess Ren. She is the Goddess of Death and Night, but this isn't necessarily a bad thing. Her followers say that life cannot come without death and death can bring life (reincarnation/dead bodies bringing about new earth). She is celebrated during the Autumnal Equinox. Her avatar is a black serpent or a black dragon. And her governing colors are red, orange, and black for the changing leaves and fire. She is also the Goddess of the West (a call out to the Wicked Witch of the West).
Using symbols helped me understand my Goddess. It also made me realize that I needed other Gods to balance her, so I have one of fertility to counter her power of death. This is a really fun way to create Gods and mess with your characters' lives.
Gods based on character needs
Sometimes the best way to build a God is determined by the needs of your characters. You may start writing and realize that your character believes in some higher power. What higher power should she follow? Well, what does she need? Is she looking for strength, guidance, answers to questions? In the Catholic faith there are patron saints that are meant to protect people in certain ways. Think of your character's needs and decide, who is her patron saint, or her patron God? From there, ask yourself if one God is enough or if you need more Gods.
The funny thing that I didn't realize about my book is that part of it revolved around my character losing her faith then finding it with the aid of a certain God. It helped give more depth to my character, and also made her more interesting. She was able to relate to me as well as to my readers. So, focus on the needs of the character and you might be able to figure out your God or Gods.
Gods who influence characters' lives
To go along with character needs, you have to consider if the Gods get involved with mortal life. Are they intangible, or do they actually walk among mortals? Do they treat mortals as equals or beneath them? If you're going to have Gods walk with them, then what should they look like? Is it hard to tell them apart from mortals? Or is it very obvious that they're big, blue, and powerful? Perhaps they have a spell on them to make them look like mortals.
You need to ask yourself these questions and see how big of a role your Gods play in the world. How little or how much they appear will determine how in depth your God system needs to be. If they're only there for the sake of basic beliefs, then you may only need names. But if you want them present, you must think how they're going to influence the world.
A final piece of advice, don't make Gods for the sake of making your story complicated. Make them have a purpose so they can move the characters and the story forward. If their presence slows down your writing, then consider cutting their appearance out.
How you make your Gods can be as complicated or simple as you want it to be. Just remember to have fun!