I want to write up some prime worlds showing off features that would effect the way they interact with the planes at large. Other write-ups and planar ideas are welcome as well as comments on these two planes.
Araloth - The world sliding into corruption.
This prime sphere has seen the rise of a great civilization over the past couple thousand years under the open rule of an arcanaloth, called "The Old Father" by his people. Overall the 'loth has been a very efficient ruler building an extensive but flexible bureaucracy that has allowed its peoples to flourish.
Outwardly the society is well ordered with minimal crime and corruption, built around a series of great cities built around mountain temples. In fact the 'loth has managed to capture, kill and bind several of the native deities of this prime impaling their forms on giant black obelisks that allow his followers to harness and use the power of their former gods. The 'loth has long term plans to slide the plane into the four fold furnace directly.
However, several powers with holdings in this and other worlds have worked together to create a barrier around the world, cutting it off from the planes at large to prevent the spread of the 'loth's power. Recently, portals to Gehenna have been opened piercing the barrier and allowing the 'loth to draw in reinforcements and the help of his fellow yugoloths.
The dominant society of this prime world is structured into many different classes and castes, based partly on birth but mostly by rank and achievements. Backstabbing and exploitation are considered to be the way to get ahead in life. Philosophically the people look to strengthen their wills and resolve, and believe with the will anything can be done; after all they've conquered the gods.
Though the levels of society are actually very complex they can be divided into four major levels: the generals, the offices, the laborers, and the thrall. The generals are the highest ranks in society and are responsible for planning and management of resources, both military and civil. The offices are the middle managers, doctors, lawyers, magi, and academics, and this level of society has the greatest amount of backstabbing and intrigue to get ahead. The laborers are the lower middle classes, and are made up of both artisans and students working to enter the higher levels of society. The lowest level are the thrall; slaves that can possibly rise in station if they show signs of excellence. Thrall are people that either live on the sparsely populated outposts of society or in the great hives that surround all the mountain cities and are commonly used and abused, worked to death or used in experiments.
In almost all cases, planewalkers from this world are from the upper three tiers of society, mostly from the second and third tier. What is striking is they are almost exclusively all arcanaloth descended tieflings. The Old Father has long instituted a series of programs to interbreed his people with both himself and others of his kind as well as programs to weed out undesirable traits. Cutters from this world are marked by a generally callous air of self-assurance and superiority. While this has led to several notable instances of cluelessness; cutters from this world have also shown potent and unusual magics and abilities that have caught several planars off guard.
The World of Veiled Stones - A prime with little separation between the ethereal, shadow and astral.
This sparsely inhabited world is made up of heavily wooded islands dotted throughout a cold fog-covered ocean. The planes of ethereal shadow and even in places the astral all seem to seep into this world, mixing smoothly that the lines between worlds are blurred.
Ruins of once great and powerful civilizations litter the landscapes of this world with roaming undead common. The very landscape seems to be flowing, with currents that can carry an unwitting traveler hundreds of miles with only a few steps and at other times keep someone from crossing a small room. A few of the islands are actually the stone corpses of dead gods, and throughout this world is saturated with magic. Wild magic effects are common.
Planewalkers from this world are rare, even though the few living inhabitants are often used to crossing between planes; there are just that few sods that survive here. Those that do tend to have more than a few drops of fey blood, and the faerie are almost as common as the undead.
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Another day another plane. Please if you have your own primes that you have thought up or used in game post them to the thread.
Okskas - The barren land of shifting sands and rippling magic.
Among the most barren of primeworlds known to the greybeards, Okskas, has at times been used as a harmonium training ground and "re-education camp." Outwardly this world is a never ending wasteland of shifting sand dunes and wind scarred rock formations. However, below the sands, occasionally uncovered as the dunes shift, are the remains of a great forest.
The only native intelligent life is a race of small insect-like creatures, called Okski, that lives on the constantly shifting dunes of the world. Shattered trunks and dried rivers can be found almost everywhere under the sands and it is amongst these partially petrified stumps that the Okski live, burrowing up through the dunes during the night and retreating down through the sands in the day.
The harmonium has little to say about this world, other than it is off limits with out a permit, and that there is little reason to go there. There are some dark rumors going around that the world has been set off limits after an expedition found the ruins of an ancient city guarded by rusting steel hulks each with a killing gaze. The only known expedition currently on the plane is a mixed party of Harmonium and Guvners working to translate the Okski language, as spells are only partially effective on the plane.
One of the most striking and interesting features of the plane is the magical nulls that sweep over its surface. All casters on the plane suffer a 10% spell failure chance at all times when casting spells, this chance rises by +5% for every spell level above second. Furthermore, all spells and magic items will fail as a wave of antimagic passes over any given area. These waves pass like the weather, moving in patterns across the deserts. For any given day roll 1d6. On a 1 there is little activity and such a wave will pass over any area once every hour or so. On a 2 to 3 the waves will pass by once every thirty minutes. On a 4 or 5 the times between waves is about 15 minutes, and on a 6 waves will pass by once every six minutes or more. Furthermore on a roll of a 6 increase the spell failure by +10% in addition to other penalties.