Hollow Moon Planetology: Blue Moon - Crystalbarrens
by Sharon Dornhoff The Crystalbarrens
By far the most unique features of Hollow Moon geography, "the
crystalbarrens" are what Materans call those parts of Maria
Serenitatis, Imbrium and Nubium, and of the great Oceanus
Procellarum, which are not a part of the Midland Ocean or its
surrounding ice-flats. They are the HM setting's answer to both
desert and tundra: cold, dry, wind-swept expanses of bare, level
crystal, dotted with islands of sand-crust or basalt cones, and lit
from beneath by a deep blue light, in the darker portion of the
lunar "day". Intolerable to most forms of humanoid life, for their
frigid temperatures and sombre desolation, they are nevertheless
home to two of Matera's hardiest and most ancient races, the cryion
bat-people and the elemental desert ghosts. The former are nomads
who cluster upon the islands and ice-flats, where conditions are
marginally more favourable and food can be herded or grown; the
latter, being dust-spirits who require neither food or warmth, are
perfectly comfortable on the open, arid wastes, and indeed they
avoid the humidity of warmer, elevated locales.
Conditions on the open crystalbarrens are arctic, windy and arid;
they also offer a few twists that conventional polar lands on
Mystara don't exhibit. Because the "ground" of the inner maria is
actually contiguous with the maria of the outer moon, the
translucent bedrock literally sucks the heat out of any unprotected
flesh that comes in contact with it, inflicting 1 hp damage per
turn upon travellers who lack protective footwear. Fortunately,
this "heat-sink" effect is only felt by immediate contact with the
crystal, and does not apply on the various "islands". Temperatures
are a steady -30 degrees F at ground level -- the same as the outer
moon's surface beneath 3' of depth -- but increase by a whopping 5
degrees per foot of elevation, as the wider, volcano-heated
atmosphere of the Hollow Moon supplants the chill that clings to
the crystalline surface. (Don't expect it to get too comfortable,
though; the mean air temperature for the HM setting, as a whole, is
only 40 degrees F, so even the highest points on the islands are
only a few degrees above freezing.) The cryions' wind-powered
ice-sledges, by which they traverse the open wastes, are built with
high prows and elevated decks, the better to keep their crews clear
of the worst of the cold. Given the odd fact that it's the ground,
not the wind, which is most likely to freeze you to death, out on
the crystalbarrens -- the opposite of what it's like in ordinary
polar regions -- the Survival (arctic) skill is of very little use
in these regions; the special Survival (crystalbarrens) skill is
required to find food, water or shelter there.
In the week-long period after fulldark, when greenish direct
sunlight shines up from the ground, temperatures climb even higher
in the equatorial region of the Oceanus Procellarum, increasing by
10 degrees per foot of elevation. It's at this time -- when
above-freezing temperatures lie just 8' above the crystal -- that
the cryions' few frost-tolerant crops can sprout and set seed on
the islands, before the sun passes beneath Procellarum's western
shoreline and the chill settles in again. The appearance of the
green light underfoot, and associated change in temperature, also
generates a thick, ground-hugging mist that condenses on the crops,
islands and cryion villages, providing the mnelds with a monthly
ration of precious moisture in an environment where springs and
rivers are unknown. The few mosses and lichens that grow below the
8' "freeze-line" on Oceanus Procellarum's islands, or in
non-equatorial zones of the crystalbarrens, must wait until storms
inundate their islands and briefly thaw out the soil ... an event
as uncommon as, and having similar ecological importance to, the
monsoons which irrigate the sere nation of Sind on Mystara. Hardy
musk-oxen and caribou browse on the lichen, and are herded by
cryion drovers.
Winds on the crystalbarrens are powerful and unceasing, and they
don't conform to the usual circulation patterns for a planet
(Matera's rotation is too slow to generate a significant corriolis
effect). Instead, warm air from the various volcanic lands
surrounding the Oceanus Procellarum blows into the crystalbarrens
at high altitudes, and ground-level cold winds blow out onto the
land. The periodic events called "circle tides" interrupt this
pattern, causing winds to alternately blow from south to north, or
from north to south, each time they occur. On Maria Imbrium and
Serenitatis, the extreme cold of the Mare Frigoris region and the
humid warmth of the Midland Ocean create a weather front that
shifts back and forth, occasionally dropping rain on the
crystalbarrens, to the relief of the Caucasus Modrigswerg and the
troglodytes of Palus Putredinis ... and to the abject horror of the
desert ghosts, to whom liquid water is deadly. (Luckily for the
Hollow Moon's oldest inhabitants, that "toxic" rainfall usually
turns to snow before hitting the ground, and is blown away
harmlessly by the prevailing winds.)
On the fringes of the Vesper Ocean, where the warmth of the
midlands peters out and the waters become icy, lie some 30 miles of
ice-flats, which have built up atop the open crystal over the
millennia. While the central ocean's pressure and submarine
vulcanism can keep its nearward regions from freezing onto the
crystal bedrock, the outlying waters closest to the edge of the
crystalbarrens are perpetually solidifying upon the chill,
translucent seabed (-30 F freezes seawater easily), only to crack
apart, sending sheets of ice bobbing to the surface. These
ice-sheets, interspersed with horizontal pockets of seawater, build
up month after month along the ocean's edge, as layers break free
of the frigid bottom. As depth decreases nearer to the shore, the
layers of ice-sheets grow thicker and thicker, until eventually the
ice becomes solid clear down to the seabed, forming an open plain
that never thaws. Seasonal spring tides wash over the ice twice a
year, and have added to and "smoothed over" this borderline. Daring
cryion sailors sometimes pilot their sledges directly onto the ice,
as the transition from crystal to ice-flats is smooth and gradual.
Level at their outermost edge, the ice-flats become broken and
treacherous as one approaches the sea, and the solid ice gives way
to ice-covered ocean. Seals and other arctic mammals prosper along
the ice/sea fringe, as the cold, oxygen-rich waters that underlie
the ice-flats foster an abundance of fish; algae to support these
fish is as likely to grow near the bottom, using light that shines
up from the underlying crystal during fulldark, as near the surface
where the Firmament's glow can reach them, the rest of the
month.
As for the crystal bedrock itself, it -- as already mentioned -- is
completely impervious to mortal weapons, spells, or feats of
engineering. Magical effects such as Stone Shape or shadow elven
tunnel-moving magics won't alter its shape, although Glassee will
render its colourless translucence even more transparent. When
sunlight shines upward through the crystalbarrens, they take on
much the same indigo glow as does the Firmament (which they should
-- they're the same material). When they aren't lit from below, the
crystalbarrens appear quite dark, offering a stark contrast to the
white of the ice-flats, to the pale mists that enshroud the
equatorial regions once a month, or to the white-furred cryions
themselves. Although dust and rock fragments may make the surface
appear coarse, the crystalbarrens are actually quite smooth and
slick; walking on these lands' surface feels as slippery as walking
on ice, except where dust or grit provide traction, and sledges,
skates, skis, and cryions' specialised skating-claws are all able
to glide across this terrain as easily as they can upon level ice.