To Fly on Metal Wings
Levium: It has been called the single most important element in our world. Its natural occurrence allows our world to exist, and its manipulation is the prerequisite for all civilization as we know it. Whether in its gaseous form (Levium) or as an ore(Levicite) it produces a strong lifting force which keeps the islands aloft despite the natural attraction to the Fog which all matter exhibits. Whether levium is repelled by the Fog, or whether it is attracted to the Mist remains unknown and, for our purposes, unimportant.
Levium gas rises, leading to very dense concentrations in the upper islands that make for rich refining opportunities. Islands with a higher ratio of levicite to mass will also tend to rise, sorting themselves according to this ratio. This differential sorting is likely responsible for the observable ‘tiering’ structure of the islands. Theoretical Geologicians theorize that the upper island belt may be the result of catastrophic impacts between larger islands in the distant past. When these islands collided they broke apart and the debris with relatively high concentrations of levicite rose to join the slowly accumulating upper islands.
Reductions in the ratio of levicite to island mass result in a corresponding reduction in island altitude. If very substantial quantities of levicite are removed from the island and exported the island will begin to sink at a rate determined by the remaining ratio. This can lead to calamitous results for the inhabitants of the sinking island, as well as any islands below them, including the continent. The removal of even a small island from its previous point can also cause unpredictable changes in wind and weather patterns. In all civilized parts of the known Aetheria levicite mining is tightly regulated and permissible under only very onerous conditions. Direct gas refining aboard floating refinery platforms in the upper islands has become the most cost-effective and safe way to collect levium for its various vital uses, but Guild control of this market still leads some to engage in illegal levicite mining; a practice the Guild energetically discourages with lethal force.
Lawful levicite mining does take place in the outer barrens under license by the Rose Queen of the Ariadne Archipelago and levicite thus extracted is used in a variety of industrial processes. For example, the Sacred Kingdom-era practice of building Sky Towers with Therium (a very light alloy of iron, carbon, and levicite) has been revived in recent years to build larger towers than would be structurally possible with traditional building materials. Therium is also used to make suits of plate armor and metal weapons lighter than they might otherwise be. Therium bullets have been employed experimentally to substantially increase firearm range. Although successful in testing, the prohibitive expense of the metal makes widespread application unlikely.
(Note to players: Therium functions much like Mythral)
By far the most high profile and dramatic use of levium is the Ariship. The history of these engineering marvels is too long to discuss here; suffice it to say that after experimenting with a variety of alternative lift methods ancient alchemaelists developed a method to increase the natural lifting properties of levium now called ‘agitation’. Agitated levium in laboratory conditions has been observed to exert more than 20 times its natural lifting force. Field application is not quite as powerful, but still allows a relatively small amount of levium to lift the tremendous bulk of an airship. Agitation also allows an airship to more precisely control its altitude while carrying inert levium in reserve. For example, an airship attempting to dive at a rapid pace (as in battle) will vent all the agitated levium in its Chamber. Absent the lifting force the ship will plunge at the full force of Fog Attraction (less the ambient levium field and the inert reserves). When the ship has reached its desired altitude some of that reserve levium will be fed into the Chamber and agitated to the level necessary to maintain the new altitude.
All levium, and particularly agitated levium, emits an ambient levium field. Any objects within this field experience a slight lifting force (much less than the force of the levium itself). Objects dropped in the upper islands have been observed to fall at a noticeably slower rate than when dropped in the middle islands. A very powerful levium field (as that exhibited by the Chamber of a super-dreadnought class airship) can slow the descent of objects very substantially.
(Note to players: The Jormungand could airdrop infantry and armordynes from a decent height without parachutes or ropes; the drop troops enjoyed an effect similar to that of a feather fall spell. Aboard smaller ships the effect is noticeable only as a +1 bonus to jump checks.)
Ambient levium fields also have a secondary effect: they interfere with each other. Agitated levium is especially susceptible to these effects and will react wildly and uncontrollably to close contact with a substantial ambient levium field. Airships which fly too close to islands have been known to lose all control of lift, plummeting or soaring rapidly and often catastrophically. Very good pilots with very talented (and quick) luftmeisters can risk travelling overland, but the closer they get to the land the more dangerous and difficult their tasks become. Trips to the continent are especially difficult, while the levels of levium naturally in the upper island skies make any trip at those altitudes treacherous.