Setting Challenge, Day 3

So I gave more thought to the background for Sunken Realms and here's what I've come up with:  There's an elemental cycle, and currently the cycle is in the Water Age.  Each race is associated with a certain element.  Currently I'm thinking of mixing the classical western elements with the eastern ones (Wu Xing), so the elements and their (tentative) pairings are Water (Halflings), Fire (Orcs), Wood (Elves), Earth (Dwarves), Metal (Humans) and Air (Gnomes).  Right now the last two pairings are something I will have to think about, because I'm not sure if they fit.  And I'm also not sure what associations to give to each element.  That will be for another time.

The cycle suggests some interesting potential plot ideas and or colour for the world.  For example, cults of the next element in the cycle could spring up, trying to hasten its arrival... or maybe the previous element hasn't quite been stamped out yet.

I also idly mused that the magic system would be different for each element.  But this seems really ambitious for a thirty days, and also gets away from core D&D as well.  I still haven't decided how close I want to stick to making it a straight up D&D game, but in that case I would be required to think of the interaction with the regular fire and forget system.  Certainly something to keep in mind.

I'm also not sure where to stick certain effects.  For example, where should lightning go in this system?  How do bards and clerics fit in?

Other idle ideas that came to me in brainstorm mode:
- There is a massive permanent storm, that slowly travels about the world.  Inspired by Jupiter's Great Red Spot.
- There is a God of the Storms, and his twin sister is the Goddess of gentle rainfall.
- There was an advanced civilization that was destroyed at the end of the last age and its great cities have been swallowed by the seas, the majority of its wonders lost.  Clearly an Atlantis analogue, and a handy source of dungeons and lost artifacts.
- I need to add in rules for naval travel, and research different ocean phenomena.
- There are a lot more variety of elementals that need to be written up.
- Aquatic races should be more common.  Mermaids, Sahaugin, etc.
- Still need to find a place for dragons...