This may turn out to fantastically pretentious, as I will no doubt remember where the ideas for the SOS came from.. It may be a way of thanking those whose brains I have picked for ideas, worlds, monsters, races and inspiration.

For my Mars planet or Seker, of course Edgar Rice Burroughs is the ultimate source. The excelent book "A Guide to Barsoom" compiled by John Flint Roywas my basic reference work. His meticulous references to the original works allowed me to provide a vivid description of the creatures and cities of Barsoom and Seker.
When the Dark Sun campaign set came out, I could see that it too was a baren, waterless, degenerating enviornment like Mars, so I modified the adventure (which I hadn't started playing yet) to include it. The Northern hemisphere of Seker is from the Mars novels and the southern hemisphere is from Dark Sun. There is a "Dead Zone" inbetween that is so deadly (no oxygen, only Nitrous Oxide) that there is no communication between them.

One of the ways to increase the physical aspects would be to use all the physical props that might work. The physical objects would be for example be rings, staffs, wands, swords and other objects that would ostensibly have magical abilities. (I tried giving out props, but it didn't have much of an impact on the players or their enjoyment of the game.)

One of the problems would be however the doubting of those involved in such an exercise. It is doubtful that people would believe that such simple means could work the necessary spell within the minds of those playing. There is no way to ultimately determine what will and will not be accepted and used by the players of the game. Not the least problem would be the resistance of the players to a situation that is obviously contrived and artificial. In reality there is no such thing as magic or spells, or alternate worlds. But in the perfect campaign, these things would be taken as axiomatic.

Dungeons and Dragons thrives on conflict. The party will be exposed to conflicts at all levels, person to person, race to race, nation to nation, planet to planet, god to god, and plane to plane. A clear structuring of these conflicts will suggest many adventures which will then be written up. At this early stage of development, this will also help codify characteristics of cults, nationalities and races. First a listing of all races and dieties will be produced. These will be attributed to their natural habitat, and perhaps suggestions for proportions found at on other worlds.

Mars:

The planets of SOS have different levels of proficiency with math.Greld of course being the most skilled, and several of the Moon worlds sharing last place. But all the worlds use the same basic system and thisis quite different than the system we use today.

The numbers of SOS are all in base 8 or Octal. Thus there are no 8 or 9 symbols in their character set. While this system might seem to have a much smaller range than the base 10 system, this octal system allows them to count to very high numbers just using the hands. This means their counting systems are different.

They count 1,2,3,4, on the fingers of their right hand. Then theystick out their right thumb and first finger to represent 5. Then 6,7 withthe rest of their fingers. The first finger of the left hand is then used to represent the first set of eight. This allows them to count to 64 on their fingers, and up to fabulous high numbers using their toes. Some sophisticated mathematicians have very flexible toes to make this easier.

This campaign could involve attention to symbolic events andappearances. While it is possible (probable?) that this element wouldescape the perception of all but a very select group (who will find whatthey are not looking for?) it may be worth the while during creation tocapture a few key concepts regarding the overall philosophy of the worlds.

For instance:

The planets of the system of SOS could be seen as possessing eachindividually the isolated attributes of Every Man. Thus, the world ofTekumel would equate to man's love of pageantry and prejudice. The world ofGreld would represent the aspect of man's separation of mind and body (themental without the physical).

Or:

If I decide to use the built in symbology of AD&D, each planet couldrepresent a specific allignment. This would/could be worked into some othercosmology without conflict.

Or:

By setting a goal to existance, we thereby define the basic objectivesof life of "right living" in the Chinese sense. Thus, the goals of a singleplayer may be preset at the outset of the campaign. If the goal ofexistance is the collection of knowledge, then travel to as many planeswould be an objective. If security is the objective of life, then politicalpower and the accumulation of wealth would be most important.

It may be that the campaign will be best served by a combination ofdifferent life goals and symbologies.

A possible problem is that in order to set up such a symbolic system,I would be forced to live within it for as long as the campaign lasted. Itmight be possible to subtly alter it as my perception ad beliefs change,but it could only change gradually and with utmost care as to continuity.

If the meaning of life is to be laughed at, then perhaps the object of lifeis to prevent the joke from being on the person. If a person has actedcorrectly in life, then the joke will be on the universe in triumph.

Giantism is said to be the result of a virus developed at one time tobe administered to cattle and chickens to increase the yield of flesh. Thisvirus was not supposed to infect anything other than the specific animal tobe infected, but after a century, the virus mutated and was caught byhumans and other species, until today on all planets, variations of sizeamong animals are still rampant. The entire race of giants is said to havesprung from the victims of the virus.

TECHNOLOGY IN SOS

The long history of SOS shows that many different degrees oftechnology have existed at one time or another. As the candle ofcivilization has burned brightly and dimly, so has the incandescence oftechnology dimmed and glowed. They do not fluctuate together so that therehave been very wise and strong civilizations that have had few machinesmore complex than a mill or a printing press. There have also been caseswhere a very high tech society has been rotten to the core.

There has to be some sort of rating system for the levels oftechnology, so I will use the system presented in Traveller. The Tech Levelindicates only the average level of an area. Thus it is possible to find atech item far out of context, like a trash to protein converter in a roadside inn without even running water. These items will usually be of greatantiquity and of unknown origin.

There will be particular cases where the entire technological outputof a nation is devoted to manufacturing a particular type of item. Usually,this is a weapon, but sometimes it is not.

It has been necessary to add some items to the standard list providedin Traveller, but the relationships are consistant. Also included in thiscampaign from Traveller are the governmental types described. Again, moredefinition specific to the D&D game have been added.

Some radical differences in techlevel vs history will be seen, butthese are those that were so easy to replicate and difficult to forget thateven a lower technology can manufacture them. Thus it is the materialsavailable that determine what is built, as well as when it was originallyinvented.

In addition to a tech level, it will be important to have a MagicLevel guage as well as the use of magic will also change from planet toplanet and even city to city. The chart below will determine this level.

stichery, machene weaving

Light Source: Refined oils

Poisons: Blended for special purposes

Level 3 Steam Age 1700-1860

Weapons Personal: Hand Guns, rifles

Weapons of War: Altillery

Armor: Light weight plate armor for infant.

Communications: Telegraph

Transport-Land: Cabs

Transport-Water: Reliable Sailing schedules

Transport-Air: Hot Air Balloons

Energy Source: Refined Mineral Oil

Luxuries: Watches, Mechanical toys

Food: Cooling Boxes, fresher foods, Canning

Medicine: Anesthetics, Microscope, Hygene

Manufacturing: Mass Production

Fabric: Printed materials, Sewing machine

Light Source: Gas

Portable Shelter: Canvas

Poisons: Gas Attacks

Level 4 Invention Age 1860-1900

Weapons Personal: Revolvers, Gatling gun

Weapons of War: Iornclad warships, Explosives

Armor: Alloy Steel for vessles

Communications: Telephone

Transport-Land: Trains

Transport-Water: Steam Ships

Transport-Air: Hang Gliders

Energy Source: Steam

Luxuries: Running water, central heat

Food: Purified substances

Medicine: Aspirin, pain killers, quinine

Manufacturing: Large scale metal works

Fabric: Water proofing

Light Source: Electric Incandescent Light

Portable Shelter: Light Canvas

Poisons: Mustard Gas

Level 5 Gasoline Age 1900-1939

Weapons Personal: Carbine, SMG

Weapons of War: Frag. Bombs, Tanks

Armor: Cloth (Bullet proof vest)

Communications: Radio

Transport-Land: Gas Cars

Transport-Water: Aircraft Carrier, Submarine

Transport-Air: Gas, Diesel airplanes

Energy Source: Gasoline

Luxuries: Electricity

Food: Frozen Foods

Medicine: Innoculations

Manufacturing: Metal Working Precision work

Fabric: Nilon

Light Source: Fluorescent

Portable Shelter: Airlifted Field Camps

Level 6 Atomic Age 1940-1970

Weapons Personal: Autorifle, Light MG

Weapons of War: Atomic Bomb, Jet

Armor: Magnesium Mesh

Communications: Radar, Television, Satalite

Transport-Land: Diesel Trucks,

Transport-Water: Hovercraft

Transport-Air: Commercial Air Flights

Transport-Space: 1 shot rockets

Energy Source: Atomic

Luxuries: World wide communication

Food: Microwave Cooking

Genetics: Initial research, Immunization

Medicine: Micro surgery, Xray, Antibiotics

Manufacturing: Integrated Circuts

Fabric: Plasic

Light Source: Chemical light

Portable Shelter: Nilon tent, plastic members

Poisons: Radiation, Custom Diseases

Level 7 Space Age 1970-1980

Weapons Personal: Body Pistol

Weapons of War: Missles, gernade launchers

Armor: Vacc Suit

Communications: Microwave, Computers