Anyone who has read our Gods & Demons supplement knows how we treat divine folks. They are “fed” by fear and/or adoration. In other words, you can pray to them to power them, you can sacrifice to give them stuff (and power), and you can simply be terrified by them and their aspect(s). Without sufficient energy gained in one of these fashions, the god will “die”.
But gods typically don’t die. They don’t even fade away. OK, they do sort of fade away, but the point here is that often one god’s aspect is very similar to another’s, and the surviving god will sort of absorb the dying god’s aspect. This works fairly well because then the surviving god gains a new bunch of worshippers. Yes, the surviving god needs to tend to those worshippers, but the worshippers are gaining the benefits of powerful god instead of a waning deity. Seeing as gods are divine and hugely powerful, they typically don’t mind appearing as the other god when they are expected to. Physical form is not that important to them. Important point - It takes centuries for a god to fade away.
So examples: Gillanae is the dwarven Queen of the gods and goddess of fairness. But the main dwarven culture has turned away from their gods, and all the dwarven gods are weakening. Gillanae was never all that powerful in that pantheon, and she is one of the first to start fading. But Laenta is a very similar goddess - Queen of her pantheon, goddess of motherhood and home, with the king having justice. So slowly, Gillanae is being absorbed into Laenta. Nobody is even going to notice. The dwarves who still worship Gillanae (the few that remain) will be worshipping Laenta, but calling her Gillanae. Laenta may over time direct the priestesses to change a few of the things they do to make certain the adoration gets to where she wants it, but overall - no harm - no foul. Even some of Gillanae’s minions have already “jumped ship” and are working for/with Laenta.
Example 2 - Suppetta Julli is the Latvich goddess of lust. Tyreabbae is the elven goddess of magical/female power. Both of these goddesses are embodiments of female power, but in seemingly different ways. Oddly enough, on a magical/spiritual level, they aren’t all that different. In fact, the two goddesses (partly purposefully and partly unconsciously) are merging. In a few hundred years, there will only be one goddess who will have an aspect of female power. She will wield her power through lust and other natural magics and have cults amongst the elves and the Lats. This has only just begun, so the elven priestesses refuse to believe that their goddess is associated with a foreign goddess of lust, but the Lats sort of get what’s going on. They have been leaving offerings to Suppetta Julli in Tyreabbae’s temples. In a very rare case, the divine may be quicker to change than the mortal on this one.
Last example: OK, we said the dwarven gods are fading. Their king Karrendock is losing power, but he has always been worshipped by some humans as the god of smiths. Quimgrow, the Dinsthain (human) god of miners is a demi-god and cannot maintain his power on his own. In a weird double shift, Brakin, king of the Dinsthains, will take on Karrendock’s duties as king of the dwarven gods, Karrendock will become the Dinsthain god of smiths and miners, and Quimgrow will cease to be. If you get the feeling that all of the dwarven gods are getting eaten up by the Dinsthain gods, you are on the right track.
OK, more on this later, but think about the gods in your game world. Any useless ones? Any ones you’d prefer went away? Any way you can have something like this happen? It might be nice and calm like Gillanae and Laenta, or it might wind up in some serious violence like Suppetta Julli and Tyreabbae before it’s done.