The slipstream is a fast moving river of air that circumnavigates the world of Jera. It is the only viable way of long distance lighter-than-air travel. The wanderers and adventurers of the world take to the skies in craft of every description.
Magic powered ships, "cloudjammers" sail the currents as well. The cloudjammers have no air envelope as spelljammers do, and do not have sufficiently powerful helms to make space travel possible. They are also a great deal cheaper, which makes them more attractive as well. The military of Mirril, the wandering cloud city, as well as that of Greymalkin use the ships for combat purposes and exploration. The Lumanites (folk of Lumanille) use them extensively for trade with the many races of Jera in areas spanning the world. The Felann have only just begun to take to the skies. Their captains are inexperienced, but their crews fight like no others on sea or in the air.
From the main current of air branch off streams that carry one to many parts of Jera. Only the most experienced pilots know all of them, much less have the skill to stay in their narrow spans. Keeping within the effects of a "stream" takes skill and some ability to detect magic.
The slipstream is a magical anomoly left over from the Elven-Mannish war. A rupture in the planes occured, such that even after the physical tears in the world were repaired, the slipstream remained. It is said that the planes involved are that of the elemental plane of air and the astral plane. The ability to detect magic allows one to see into the astral plane, where force lines run along the wind currents. In wider streams, this talent is helpful, but not really needed, as the effects of the slipstream do not end abruptly and one can feel their way through the eddies and back into the mainstream. With minor currents, this is not possible. They end abruptly, and can often end temporarily, only to take up again a mile or so later. These lesser streams are the tradewinds of the magically aware. Guides hire out their services to the highest bidders, often retiring early in life from the tremendous earnings possible for one such.
Adding to the adventure of the "windwalker" are deadly obstacles to avoid. Riptides and downdrafts exist that can thrust a ship downward to its demise. Whirlpools can arise along the stronger streams capable of tearing a ship apart, some of which can pull one into fissures through to the astral plane, especially over Dietroch, a continent known for its magical instability.
In addition to these perils of the wind itself, many of those that travel the slipstream come not for adventure or discovery, but to kill and plunder. Probably the most notorious of these is Count Safrack, undead lord of the skies. He commands the airship "Crypt Ariel," a converted Dwarven spelljammer, a floating mountian. A collossal castle tops the mass of stone.
From his lair, Safrack sends his minions out on missions to enslave yet more undead to work in his service, eternal service. His forces attack unwary ships from kites tethered to the mountain. The kites have moveable rudders and alierons that allow them to manuver quickly in the slipstream. The flying minions of Count Sareck number nearly a hundred in number, many of them spirits of one sort or other, though many of them cannot bear sunlight and are only useful in night raids. Sareck himself is 3/4 pureblood vampire. He can remain outdoors only through use of sunglasses with sideshields.
The count is very into style and luxury, and often mixes unbenown to those around him in the societal circles of the upper crust of Alexander and Grunburg. He shows up for costume balls mostly, where his identity can be safely hidden when his victims begin to appear the night after. The count has been known to rob banks and foolishly spend the money decorating his castle and its grounds. He is quite a character, and is especially charismatic, the type that you'd like if you met him at a party. He just has few friends; living, that is.
A gang of 'punks with a knack for piracy, the "desert rats" are yet one more peril to flight in the slipstream. Most of them are central to Asterland, but some have been sighted as far east as Gannet. They ride their heavily modified lithel birch hoverboards, which they equip with a triangular sail. On these, the punks can outmanuver any ship in the sky. They make their living through piracy of the heavy-laden merchant ships that make their way around the world. They are led by their leader Chess Fakkra, a harlequin master with the use of limited magic. He is shrewd and cunning, and a master of disguise. His dexterity has grown with the quaffing of contraband potions heisted from the Freedom Society. With the scimitar, Chess has no equal. His nerves are so wired that he cannot sit completely still, but in a fight, he is but a blur of death-dealing fury. None of the "rats" have ever dared challenge his claim to the leadership of their band.
Not all of the creatures that ride the winds will chew you up and spit you out. There are a number of creatures that have adapted to the high winds and made them their preferred home. Among these are the various species of "floaters," docile jellyfish-like creatures that fill with warm air and float in the jetstream, feeding on insects that get caught up in the currents. It is said that they feed on the trace etherial energies of the flow. Those that know claim that they taste very good if prepared fresh in wine sause, and the Felann consider them a delacacy.
Spectral rays race alongside magic helmed airships, feeding on the residual magic. They are native to the astral plane, but venture into the material plane for periods of a few hours or less. Sailors claim that they are a good omen, that luch is coming your way.
The path of the slipstream varies little from year to year. It crosses the
Vale of Titan Eagles, heading southeast straight through to just north of
Geyon, where it winds its way up and over the mountains, finally making its way
out to sea after passing the Vale of Industrious Dead some two hundred miles
to the south.