So, gods and deities. They're procedurally generated like a lot of things in the game, they have their own spheres of influences and I believe that they either hate each other or don't really care and only want more worshipers of their own (if not directly).
With the new progressive history system finally put in place and magic being a topic for discussion as always, I got a rather expansive idea in regards to the religion part of DF's worlds, which I promptly dubbed "War in the heavens".
Currently, we have some greater scale mechanics and features already put in place, with armies moving about the place and whatnot. However most of these seem to largely driven by earthly needs or conflicts, and larger scale conflicts on the religious background don't really happen if I'm not mistaken. However, imagine that the various deities that one's worlds inevitably end up with could be just as mischievous as the mortals, with their own personalities or rather, a set of preferences and dislikes which could drive them to create godly alliances between each other (aptly called pantheons for the sake of this thread) and possibly wage war against other deities they don't particularly like (since for instance deity A could be much more self-centered than deity B since deity A wants to be the only deity of fortresses and metal but deity B is also a deity of fortresses and metal, with significantly more followers than deity A).
This would allow the deities to contact their followers and tell them to fight against the followers of other deities (though for that one would need to first have a way to distinguish between followers of certain deities, and adding a conversation option for that would be a nice thing to have) to please them, and the deities could reward or punish their followers if they're particularly (un)happy about the results - ranging from sending down curses and nasty plagues onto their worshipers if something went wrong to artifacts, powerful beings or even stepping into the mortal world themselves (assuming they don't do that already, barring the posers).
Such a system could also tie in nicely with whatever magic system we eventually end up with - if magic was of godly origin, then mages of a stronger deity with more faithful worshipers would have access to more powerful magic than the lesser deity with few to no followers. (
though if you want to discuss that, I guess this is a better thread for it)
This would also give people (priests in particular) a meaningful reason to actually talk directly to their deities, though I don't think that a deity would be willing to, say, trade. Unless it's a god of death in which case you could your soul (whatever it might mean in the gameplay sense) for some powerful godly things, but that's loosely tied to this thread.