Making a New Crystal Sphere (Spelljammer Supplement)
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01-95 Standard system (as shownon system display).
96-00 Special system (roll again on following table or choose
01-20 Fixed system
21-30 Random movement
31-40 Semi-random movement
41-70 Single planet (roll no further)
96-00 Nested spheres
01-70 Sun (fire body)
71 -95 Planet (roll again)
01-80 Earth body
81-90 Air body
91-00 Water body
96-99 No primary; the planets orbit an empty spot at the center
00 Portal to another plane(roll again)
01-30 Outer plane
31-50 Plane of elemental fire
51-60 Plane of elemental earth
61-70 Plane of elemental water
61-80 Plane of elemental air
81-90 Positive material plane
91-00 Negative material plane
Number of Planets
01-05 One planet
06-10 Two planets
11-15 Three planets
16-20 Four planets
21-30 Five planets
31-45 Six planets
46-55 Seven planets
56-65 Eight planets
66-75 Nine planets
76-85 Ten planets
86-90 ld20 planets
91-00 No major planets; entire sphere has small planetoids, debris, etc.(roll no further)
01-95 Planets are worlds orbiting around a central point.
96-00 Planets are carried on the backs of large worldcreatures which carry the spheres about.*
• Planets carried on boats sailing on a sea of wildspace, or even water
• Planets mounted on the tops of infinitely tall pillars. Anyone who sails downward can travel indefinitely without ever reaching the bottom
• Planets mounted on enormous,clockwork gears
• Planets tumbling eternally downhill. Even after making one complete trip around the primary body, they are still rolling downhill(who can explain such mysteries?)
• The sphere could be divided into two distinct and separate hemispheres with completely different systems in each. The systems could be divided by a flat ocean which stretches to the limits of the sphere, or by an extension of the sphere material itself.
01-10 No movement—fixed planets
11-15 Random movement within sphere
16-50 All planets move clockwise in orbit
51-90 All planets move counterclockwise in orbit
91-00 Each planet moves
counterclockwise (51 -90)
roll for each Planet
Roll Percentile Dice:
01-40 Earth type
41-60 Fire type
61-60 Air type
81-99 Water type
00 Liveworld (optional)
Fire and Air Types
01-02 Size A
03-05 Size B
06-10 Size C
11-20 Size D
21-35 Size E
36-50 Size F
51-70 Size G
71-85 Size H
86-95 Size I
96-00 Size J
Earth and Water Types
01-05 Size A
06-10 Size B
11-20 Size C
21-40 Size D
41-60 Size E
61-80 Size F
81-90 Size G
91-00 Size H
Goodies(optional) moons and other fun
01-10 Single moon. Also roll again, ignoring a second result of 01 -10
11-20 1-4 moons
21-25 1-4 moons and roll again
26-35 Cluster of asteroids
36-45 Ring (earth)
46-55 Ring (fire)
56-65 Ring (water/ice)
66-75 Planet hotter than normal
76-85 Planet colder than normal
96-99 Civilization—world empire
00 Roll twice
Explanations Moon: Moons will be no larger than one size smaller than the planet they orbit (moons orbiting size A planets are also size A). Other attributes are set by the DM.
Cluster: Similar to a moon, but consists of a tight bundle of asteroids in a close orbit around the planet.
Ring: Rings can be asteroid belts, frozen water, or ribbons of fire.
Planet hotter than normal: When laying out the planet, give it lots of baked deserts, steaming jungles, dripping rain forests, and tropical swamps.
Planet colder than normal: Locked in either a permanent or temporary ice age. Wind-swept mountains, drifting snow, and glaciers are the norm planet-wide.
Vacuum: Most worlds have an atmosphere of some type, but there are exceptions. Only water and earth-type worlds can have this attribute. In the case of earth worlds,the planet's surface is exposed to raw, lifeless space, while on water worlds, there is usually a shell of ice covering the water beneath.
Civilization—world empire: Most fantasy worlds are mired in the Middle Ages, with a huge number of small, petty states and warlords. Fewer are capable of creating a continent-wide string of nations and very, very few are under the control of a single leader or group of leaders.
Part 5: Planetary Placement Start at the center of the system on the inner orbital track and roll Id6.
That is how far out (in rings) the first planet is. Repeat the process for each planet beyond the first, counting out from each previous planet.
When the planets being placed move out past the 200-million-mile mark, go to the outer track.
The next planet will be in the 400 million mile area. Continue the procedure using a four-sided die until you run out of planets.
The crystal shell of the system will always be as far from the outermost orbit as that orbit is from the primary body of the system. In cases of randomly moving planets, use the outermost planet's set-up location as itsorbital distance
|planet display. Source|
For those the need a quick random system http://lost.spelljammer.org/RandomCrystalSphere/