The below mentioned major time-line realities are fixed to the Abode. It is naturally possible to make connections to parallel realities of these as well, but this is generally avoided, as most "side-track" realities tend to fall back into one of the main realities again.
The names are only used in a descriptive way, it would be pretty confusing since all these realities would see themselves as the "real" Earth.
In the below realities use of magic is more or less commonplace, and considered part of science. In most of them humanoids, like elf's, dwarf's and goblins, live parallel to humans.
The names used here are the names used in the Abode to mark the portals, usually referring to the place where the portal is located (like Avalone), the continent (like Hyperborea), or description of the time line (Imperial Earth). In most cases the inhabitants of each plane will simply refer to their own as "Earth" or something similar. You wouldn't know what they meant if somebody asked you how things are on Clod, would you?
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Avalone: A medieval setting where classic history was much like ours up to medieval times. In this reality magic and mythos have had a great influence on history and science. The setting is close to romantic medieval (think King Arthur), at least from an outsiders view. The world is ruled by a mixture of theocratic and magocratic governments, who appoint the rulers. The Magic Council resides here, on the island Avalone.
Current nave reality for the Abode, even if it is not any of the worlds the Abode originates from. The Old Magician is connected to the Magic Council here, but probably does not come from this world.
The elf Erendil and Saber are from this world.
Hyperborea: What most people would describe as a more barbaric world (think Conan's world). High involvement of deities and magic from early history, somewhat parallel to ours until about 2500 years ago. Despite being called barbaric, this world is highly advanced when it comes to magic technology. It's also one of the worlds where dragons still reside on earth.
Alma, Bel, Lir and Rook are from Hyperborea.
Sylvan Earth: In this reality European civilization was nearly wiped out after the great diseases where brought back from the West Indies in the sixteenth century, only a close collaboration with the advanced medical expertise of the Americans could save them. The society after that grew up to a sober industrialism, much affected by the American Indian traders that came to dominate Europe in the seventeenth century. The rich Indian nations are trading both westwards (China) and eastwards (Europe) and have been striving to maintain a peaceful equilibrium. An interesting observation is that the wheel is not considered as an important innovation in this world.
Sus originates from this world.
Imperial Earth: An earth where the great Empires like Britain, France, Russia, China and Japan rule. History is close to ours until the beginning of the nineteenth century. Important points are that these countries kept their hold on the colonies. After the Sino-Japanese wars 1895, the former Korean empire surrendered to Japan and came under Japanese rule, China under their Empress succeeded in opening up new trade routes and have became great enough to rival Britain. There is some resemblance to Jules Verne's stories to this world. An important note is that the Otto Cycle engine and Edison's light bulb where considered a failures in this reality, leaving room to other technological advancements.
Ren, Li Nichang, Pearl and Shiomi come from the Sino - Nihon empires area of this world.
Steampunk Earth: Much like the Imperial Earth above, but where Europe and US developed a highly advanced steam and fuel cell based technology.
Two versions of this reality are frequently visited by Tomomi and Shinju who likes their market places.
Biopunk Earth I: Much like the Steampunk and Imperial Earth, it's a reality where biochemistry and biophysics are central. Here genetic and bionic science developed early and advanced fuel cell technology dominates as energy source for vehicles and portable electronics. Digital equipment is well developed and includes use of organic and quantum computers. Needless to say this world has some of the most advanced computers and bionic enhancements available as well.
Shinju-ichi comes from this reality.
Biopunk Earth II: Very close to Biopunk Earth I above, but with a different and heavier focus on biologic research, as well as cloning. The difference is very small however and if it were not for the Shinju "twins", would not be separated here.
Shinju-ni comes from this reality. Both versions are frequently visited by both Shinju's and Tomomi.
Thule: A sparsely inhabited semi-barbaric version of earth, where the dark ages still rule.
Used as a retreat by Old Magician (and other inhabitants of the Abode).
The Great Empires: On this plane the first Roman Empire ruled over one thousand years, and set up trade routes with India and China in the east and the Indian Nations in the west. Already 800 years ago they had men walking on the moon, but gave up space travel when developing an advanced form of plane travelling that superseded physical movement over long distances. The plane is considered dangerous to visit for those not familiar with its history and customs.
Shade frequently visits this reality, but it is not her "home" reality.
The Classical Age: Much like the Great Empires, but where the Mediterranean culture continued to bloom into current time.
Calandra and Palatyne are from the Classical Age
The Great Kingdom - Oerth: A reality far from our own, where magic and high adventure rules, at least that would be our perception of it (given that we would survive more than a day). In this world humanoids and demi-humans abound, as well as dragons and other fantastic creatures. Apart from the fact that they don't even call their planet Earth, which by itself is unusual, it is also one of the alternate realities where they have two moons, the larger almost identical to our moon in behaviour, and a smaller, blue moon, called Celeste with an orbital period of three months.
Lady Ree and Evaleigh come from the Great Kingdom, Wotatease is from Oerth as well and it is well known that our Hyperborian gang has been adventuring there.
Shadow Earth: An earth ruled by a strong magocracy, using demons and dark arts to subdue others. The portal to this reality is heavily barred to prevent unauthorized access from both sides.
There are unconfirmed rumours that Shade originates from Shadow Earth.
The Reich and the Crown: A reality close to ours where the second world war ended with a peace treaty between German, England and US after the assassination of Hitler 1944 and the consequent replacement of the political top. This treaty gave Germany control over most of the European mainland, and gave them possibility to strengthen the east front. The Soviet did not submit to a peace treaty until 1945 when Germany dropped two thermonuclear bombs in Siberia to deter them (and to show of its capabilities for the US and Commonwealth who had tried to weaken the German influences in central Europe). The result was a divided Poland and split Warsaw. In this world cold war and espionage is at its peak, with a complex political game going on between EDU, US/Commonwealth and Soviet/China communists.
Alma and Bel seem to have been quite active here over several years
Clod Earth: The reality that you are in if you read this (the wonders of spatial internet). A place with little to none magical influence, most known for its high level of ignorance of most things (like magic, nature and possibilities of other worlds), ruled by rather boring economic politics. Their society is considered as mostly harmless for all except itself.
Tomomi was "rescued" from this reality.