Here's an idea, not so well formed yet, but...
What if there is a shortage of food, somehow? The Weather goddess gets annoyed that the folks of Yliakum don't even notice when it rains, snows, or turns to a thick fog. She bans the release of water on the third level. (set up) (GMs or the wonderful weather folks could just make these things happen as they will and when they have time.)
Now, Kada Els and Brado are out of food.(GMs could 'stop' the ability of folks to buy food from NPCs for a time?) Folks are hungry. Folks could join together to plant a community garden, or gardens. Cooks and bakers could make goods until their raw supplies run out. Some guilds will open their gardens, and have weekly or monthly or spontaneous gatherings where all bring what they have, and all share the food and festivities. Some guilds will plant, and guard their plots with their lives and swords. Some robbers will sneak into the food stores and steal, and sell foods at exhorbinent (sp?) prices. (lots of on going small or larger RP opportunities)
Caravans are gathered to go to the far reaches of the land, harvest what they can, and return to sell in the towns. The ulbers and clackers are starving too, so they might attack caravans of merchants with their meager harvests.

(for those who like to slash and kill)
Now folks may start dying from starvation. Perhaps the healers and mages start clinics to care for the young, the elderly, the sick. Herbalists make potions to reinvigorate people's systems. (Perhaps some of the existing magics could be used?). Some folks are altruistic and help anyone in need. Some use the crisis as a way to gouge folks of their tria. (more RP opportunities)
Perhaps an oasis is found, far far from an existing town, with a spring of fresh water like Xiosia's garden. Perhaps the waters have healing powers, like Lourdes? Will it be opened to all?
Perhaps the priests of Lanaxx will claim it as their own, and conduct rituals for only the faithful to be refreshed and revived? Perhaps the followers of Talad will war with the followers of Lanaxx? Perhaps the Daughters of Xiosia will try to mediate all? Perhaps the royal house of Purty will take it upon themselves to protect the spot, and allow all in need to enter?
How will we all deal with this crisis? How will folks feed their loved ones? How will the guards and the guilds react to an overwhelming, environmental crisis? Will the gods intervene? Will the Ochtarchy ration goods? Will the robbers and thieves try to kill off the law abiding citizens? Will yulbers be at risk of being stolen and eaten? Will children wither? Will those weakened from not eating not be able to mine platinum anymore? will all the world wide money tria supply dry up? Will there be nothing to buy?

Just an idea for extended rps in which everyone might do what their character would do in such a crisis...

{Roled is Still trying to get back into the game. Bought a new computer with Ubuntu. A great friend came, set up Linex so it would read PS, and unpacked PS for me, but the graphics card is insufficient to run the game. Have to buy another graphics card. Have to work to get enough $$ to buy another graphics card. May have to dowload updated drivers. {{Thanks Pizik for last time...}}Many thanks to all those who continue to try to help me. Roled Rolak continues to wander alone in the desert. It's been almost 40 days.... Roled misses his home!}
Yers,
RR