I am actually very interested to see how magic, enchantments, curses, diseases, etc. are going to be handled:
There could be preset curses/diseases that could be used by different entities or civilizations. An Elven Druid could punish an excessive Dwarven Logging Industry by cursing a mountain range, so that the trees uprooted themselves and stormed the Fortress. Perhaps a god of the hunt could take notice of a legendary hunter, who has killed and butchered inordinate amounts of cougars, and grant them the form of a powerful, but Hostile, Cougarman, so they could sit back and either watch the carnage, or make the hunter become the hunted.
Alternatively, I could see procedurally-generated material for curses/diseases too. It'd be neat to gen one world with a malevolent Wizard named Nilus Verminplague, who had the power to instantly transmute any pools of water near him into massive swarms of Flies and Blood Gnats, and then gen another world where the Wizard Mendok the Thunderous lives among Humans, battling against their foes by hurling orbs of sonic force that would blow anything they struck into scattered chunks.
Random diseases with randomized symptoms would be pretty cool too. One disease may cause periodic organ damage, sleeplessness, and loss of hair cosmetic layers, while another may change skin layers into insect chitin, or blood into liquid fire. If not successfully treated in a hospital, they could also have effects that would grow more severe over time, such as causing berserk spurts culminating in a rampage, or limbs turning into silver one by one until they become a Silver Statue of themselves.
Heck, give it enough span, and diseases that turned the infected into a valuable metal, or an unstoppable berserker, may even be infected purposefully by less-scrupulous players.