There aren't exactly Gods, per se, though it's said in other ages there were.
Instead, there are countless demi-gods, demons, magical aberrations, spirits, and charismatic mortals that are revered around the Dragon Empire.
Legend has it that the power of these "gods" stems from the depth of faith and loyalty in their followers – the powers of gods wax and wane in sync with their worship.
Thralls of the One-Eyed Lord
The Lich King's agents are ever at work across the Empire, wearing away at the magical wards that keep him imprisoned. Fanatics promised life unending have been exposed at every echelon of power.
The architecture of the Nine Hells predates the Diabolist, stretching back to the first nightmare. Animated wastelands and maddening architecture play host to aberrations beyond number. When a malevolent trickster spirit works enough will up to make contact with the mortal world, they draw in worshippers through lies, secrets, and dark dealings. Cells devoted to obscure, depraved demons work in silence across the map.
The Diabolist is the most organized and motivated of the demons, and the Hell Holes are hers. Her strength is derived from her worshippers, and there are forsaken parts of the Empire where wizards serve her openly.
Cult of the Devourer
They have a ritual that draws the Stone Thief, but to what end? The invocation is in no known tongue, some dead and decayed branch of magic. A heavy artifact is used to pound the earth during this ceremony, calling the Stone Thief through the earth.
Some agents have moved to recover the Eye of the Stone Thief. It is believed that the Stone Thief can see through the eye anywhere, and that its holder can command the malevolent aberration to do their bidding.
The Sorceror Wild insisted that a clan of wizards live inside the Stone Thief.
Cult of Talos
Talos is just a dude who believes in hard work, honesty, and righteousness. He's invisible, and he can only be heard by a single living being – Styx, the gentle monster who has set forth into the world to share Talos' news.
A small church was built in Talos' honor in Eldolan, on the site where a theatre once burned to the ground.