The Silver Void setting is one in which swashbuckling adventurers might travel to distant planets, battle space monsters and otherwise strut their stuff in front of green space-babes. But real-world space is a super deadly realm. It is an extremely hostile environment. It has no gravity, is airless, super-cold and has
high levels of radiation strong negative energy trait (check the Blood and Treasure GMG page 20 for details). So to avoid all of the arguments and struggles of inserting real-world space travel into a fantasy game, I am circumventing it all with the following:
SILVER VOID COSMOLOGY
In the Silver Void setting, space travel is most often done by travelling through the Astral Plane. The Astral Plane is the "space" between the planes and the spheres (planets etc). It is a great, endless "sea" of clear silvery sky, both above and below. Stars, planets and constellations can be seen, though they are not always those of our own dimension, so travelers must beware. The Astral Plane has subjective directional gravity. It is also timeless. Age, hunger, thirst, poison, and natural healing do not function in the Astral Plane, though they resume when the traveler leaves the Astral Plane.
Ships and creatures looking to enter the astral plane must be able to reach the very edge of a planet’s atmosphere (50-80 miles up) to attempt to breach the astral barrier. This requires specially made vessels with an Astral Helm (see below) or powerful spells.
TOOLS OF THE TRADE (STANDARD EQUIPMENT)
What powers a ship is a complex assortment of conjoined magical devices, built into the structure of a vessel. In many ways the end result is a melding of archaic seagoing vessel and a submarine or other designs. Ships designed to ply the starry deep are usually equipped with the following:
ASTRAL HELM: All vessels will have a Helm, which is basically the steering wheel of the ship. From this position, the ship can be steered and controlled. A helm appears as a steering wheel, often with a specialized chair.
When in combat, the helm allows the pilot to propel the ship by thought at a speed (in feet) equal to 10 times the pilot’s Intelligence score. When the ship passes within a gravity well, such as that generated by an asteroid, moon or planetary body, it slows to a speed of 50 feet. Many ships have additional or alternate means of propulsion and flight for emergencies and to operate in a gravity well such as balloons, spells, psychic sails, wings or special materials.
PLANAR CHART AND SEXTANT: Usually attached to the Scryscreen (see below) or in the captains quarters, this device allows a spellcasting crew-member to chart a course across the Silver Void. It is effectively a map with special map symbols. Most are very mechanical in appearance, much like an astrolabe. When setting a course to distant worlds or stars, the Helmsman must make a Decipher Codes check. Success allows the vessel will take 7d10 ship days to reach their destination, regardless of travel distance. During this time the crew need not eat, drink or sleep, though many still do to repel the sheer weirdness of the Starry Void. Failing this role indicates the ship going off course, and ending up at the wrong destination (GM's choice).
GENESIS MATRIX: This integrated wondrous item has a control panel about the size of a treasure chest (often mounted on a wall), and maintains the ships gravity and atmosphere. In game terms, a functioning Genesis Matrix system turns the vessel into a mobile demiplane, with the ships environment being "set" like the Genesis spell (see Blood and Treasure GMG page 89-90 for details). This device is not often found on vessels crewed by astral races, primitives, constructs or undead.
SCRYSCREEN: This is a “magic mirror” that projects objects in front of the vessel as well as allowing communication between ships. This item is located on the bridge, in front of the Helm. Any divination spell used by the helmsman is maximized when used with a Scryscreen.
Ship basics, astral combat and sample vessels.
These rules use the wonderful Blood and Treasure tabletop roleplaying game by John Stater. Its a fun and easy RPG made with the basic D20 system but hearkening back to old school sensibilities. Check it out. All the cool kids are doing it.