The Labyrinth Worldbook is Kobold Press's planar setting for Tales of the Valiant or any DnD 5e variant. This is my review of chapter 6: Pantheon of the Labyrinth.
Like magic, I personally don't think you can ever have too many gods in a fantasy setting. I was always fascinated by mythology as a kid, with my first interest being the ancient Greek pantheon because that's what you got in school by default, and then in the ancient Egyptian pantheon because it felt like the pantheon-they-don't-tell-you-about in school. Also, you can't be raised in the USA without internalising Judeo-Christian mythology, and if you're really into research then you end up with a bunch of Dante and Jewish expansions. Even a mediocre pantheon is usually of interest to me, so the pantheon chapter of the Labyrinth Worldbook can essentially do no wrong. That's a good thing, because so far the concept of the Labyrinth is pretty muddled. It's a series of pathways between worlds, not a world itself, but a painfully generic fantasy city called the Smithy is its hub, and there are encampments and cities within the Labyrinth, which isn't actually a labyrinth at all. For once, I think a nice look at a cosmological pantheon might just help this setting feel grounded.
The pantheon presented in this book are the gods known within the Labyrinth itself, and on some of the core worlds of the Labyrinth. There are 6 gods, and 9 dark gods.
If you're already a fan of the Kobold Press setting of Midgard, and specifically the Southlands, then some of the gods of the Labyrinth will be familiar.
It's a short list, but there are obviously plenty of gods in other pantheons that would be just as relevant in the Labyrinth. For characters born and raised in the Labyrinth, or very used to traveling the Labyrinth, these gods would probably be familiar.
As with the gods of the Labyrinth, some of the dark gods listed in this book are from the Southlands.
Obviously there are plenty of other gods you could use in a Labyrinth adventure, and the final section of this chapter lists 20 of them. I recognise most gods in this list from the Southlands and the Northlands, and I wouldn't be surprised to find the others in the main Midgard source book.
This is very much a source for all the other cosmological domains that inevitably come up in a campaign. Fortuna is the goddess of fortune and luck. Ninkash is the goddess of beer and community. Hecate is (another) goddess of night and magic. Of course there's Bastet, the goddess of felines. And several Northland gods are listed here, including Fenris and Wotan and Loki.
There are a lot to choose from, each with just enough detail to help you fake your way through questions about the faith.
Gods are a quick and easy way to give character to a world or an NPC. As a player, when you hear about a god you're unfamiliar with, your mind is flooded with questions and ideas. Who is this god? What does the god demand of its followers? What does the god promise in return? Why do people here worship that god?
It's instant world building, and as a game master I love having interesting gods to choose from. In my experience, Kobold Press has always been really good at creating interesting gods. Nothing's ever simple with Kobold Press gods. Any one god can have a seemingly unrelated or even conflicting collection of interests. They're complex and unknowable, and there's rarely one that feels exactly right for any given purpose. And that's pretty perfect, because contradiction and conflicting interpretation is exactly what religious faith is about.
I don't use many gods in my planar adventures. Having discovered inter-dimensional travel through Planescape, I'm a fan of the idea that once you step outside of reality, gods that are isolated by crystal spheres floating in flotsam just don't seem that powerful any more. But it's an intriguing idea that in the Labyrinth setting, there are those gods that wander the space between worlds. It's not an idea I'm exploring in my Labyrinth Adventures campaign, but it's nice to have a different take on an inter-dimensional setting and gods.