We need to have periodic posts summarizing the setting as it has been created so far. For instance:
The land is broken into a number of little islands surrounded by a sea of volcanic fog (and ash, judging by later things). It is filled with the souls of the dead (hence the common tradition of sending corpses of the dead into the sea); their siren songs drive men living by the coast mad. The tides are the only natural way to mark time. The islands "evolved" (formed?) from volcanoes. The largest group of islands surrounds an obsidian spire that reaches to the sun, which some dwarves believe was made by the humanoid molds. Every 50 tides, the dwarves (who have a curious affection for the spire) hold a ritual of bravery which involves ascending the spire. None return; eventually, the heat of the sun incapacitates the ascendant champions, and they collapse and die. It is believed, however, that the dwarves have reached a kind of promised land, where the air is pure and without poison. Underground, there is an extremely valuable metal known as orichalcum which is believed to have fallen from the sun. Dwarves have made several expeditions to find the source.
The air is poisonous, similar to Venus (but presumably not quite as hot, dense, or...acidic as Venus's, not as prone to permanent continent-sized storms, because screw Venus).
The sun is in a stationary position in the sky; this is because the world is on the inside of a hollow sphere. Outside the shell is Oblivion; anything thrown there is destroyed and ceases to have ever existed. Traitors are typically tortured before being sent into oblivion. Some claim there is a second sun called the moon, but none in living memory have seen such a thing.
The volcanoes are inhabited by a species of sentient lava (magma?) squid. Other sentient races include maggot-men, a hive-minded humanoid mold, and dwarves (known for their fine handiwork and craftsmanship, as well as coordination (better than the hive mind?) that makes their ability to create large structures second to none). A race of intelligent, though perhaps not quite sapient, trees is also present; their boughs shield some areas from the harsh atmosphere, creating habitable areas underneath. Given that they also block the light, though, no plants can grow there; inhabitants of these "habitable" areas need to venture out to get food from the surrounding areas. The trees and the mold have an antagonistic relationship, due to the trees absorbing their kin.
Maggot-men live under the rule of a single Lord. The lava squid do not have any formalized government, instead operating on a tribal system, with popular "big-squid" and the occasional elected Chief who rules several schools. The molds do not have any kind of central organization, nor do they need one. Dwarves are fractured into a number of feudal states.
Ash creatures live in the sea (not just big ones); the large ones are worshiped as gods in the outer isles. Some believe even larger creatures slumber beneath the lava (magma?); others believe the whole world is on the back of a very large such creature. (See more below.) There is also a species of ash-living, soul-eating "jellyfish" evolved from the magma squid, which uses "heat-pouches" to swim through the sea.
There is a religion known as the Akupara which believes that the world is supported on the back of a giant creature sleeping under the magma, and which fears that it will one day awaken and shake the world off. One sect is dedicated to preventing this threat, while others typically accept this as an inevitable--perhaps not even a bad--fate of the world.
The setting is slightly disturbing.
Parentheticals are guesses as to interpretation. Bold things are things I added.