Biplanes cross the skies. Spies, journalists, and detectives haunt the smoke-shrouded streets of floating cites. Expeditions to distant lands, fistfights in implausible locations, cigarettes, newspapers, and schemes. Yes, it's time for some dieselpunk.
This post is stream-of-consciousness worldbuilding. The next post in the series will (hopefully) contain more gameable content. I've tagged this post "OSR" for now, because I'm considering building a Sky Pirates GLOG hack (or something similar).
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| Juhyung Kang |
The Curse of Count Zeppelin
There's a time-honoured rule that if your film features a jet ski chase, it will not be good. Perhaps there's a similar rule: pulp-inspired media with sky pirates is almost guaranteed to be bad. A zeppelin is usually, but not always, a a harbinger of critical doom.
The Ghibli films Porco Rosso (1992) and Castle in the Sky (1986) are exceptions. Miyazaki's deep love of aircraft helps. It's unclear if the same rule applies to RPGs and board games, or if any sufficiently niche setting is doomed. Crimson Skies did well, but CGL's Leviathan is a notorious white elephant.
If the curse is real, then, if you're going to run a sky pirates RPG, it makes sense to minimize effort. The internet is littered with the wreckage of dieselpunk / sky pirate worlds, built with lavish care and forgotten by almost everyone.
Plausible Fictional History
The more you learn, the more difficult running a historical RPG becomes. The paralysis of detail, the desire for verisimilitude, the reasons X won't work, the doubt over whether or not aluminum foil came before or after music over the radio,* can combine to paralyze a thoughtful GM.
*Aluminum foil first, by about a decade.
It's far easier to use a fictional setting. You can make sweeping medieval generalizations, run pirates without trying to remember who was in power in Spain, or compress an industrial revolution into a gameable form, all while cheerfully ignoring signals from certain parts of your brain.
Aircraft-based pulp settings are usually alternative histories. Crimson Skies has a disunited USA, Sky Captain and the World of Tomorrow has... a '30s cold war (?). This lets authors have Chicago, jazz, and kewpie dolls, but also aircraft-carrier-sized zeppelins and biplane-piloting mercenaries. Kenneth Hite is, possibly, the leading RPG authority in this genre.
Hite's Law: All Change Points, from Xerxes to the last presidential election, create worlds with clean, efficient Zeppelin traffic. Changing history may produce Zeppelins as an inevitable by-product, much as bombarding uranium produces gamma rays. Often, the quickest way to tell if you are in an Alternate History is to look up, rather than at a newspaper or encyclopedia. From this premise, it is not outside the realm of Plausibility that our history between 1900 and 1936 was, in fact, an Alternate History. It would, at least, explain a lot.
-Kenneth Hite, "An Alternate-Historical Alphabet," January 14, 2000
Other games take a different approach. Bloodborne, Disco Elysium, the Age of Steel RPG, use real-world visual and linguistic cues (cathedrals, the police, etc.) in an entirely new (or largely implied) setting. You can use real-world knowledge to figure out what the Regnum Cocainum of King Phillipe III was like, without any additional information.
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| Erik van Helvoirt |
Sky Pirates, Hold the Sky Piracy?
I don't think a game about sky pirates should be built around air combat rules. Those rules are good to have, just like sailing ship rules are good for a pirate game, but making them the core of the game requires a combat-as-a-sport design mindset. It's better suited to a wargame or a video game (or a specialized game, like Lancer). RPGs are about schemes. Combat-as-a-sport is about optimization.
A scheme is using a pig bladder, a ladder, and three pounds of marbles to turn a hopeless fight into a total victory. Optimization is about using your +1 fire sword with an amulet that doubles your dealt fire damage, a vest that turns fire damage into acid damage, and a class feature that lets you apply acid damage to all enemies in a 30' radius... Schemes rely on the shared imagined reality of the game. Optimization relies on the rules. A shared imaginary reality is the draw of RPGs. You can get rules anywhere.
Incidentally, Flying Circus would probably work out-of-the-box for my purposes if I wanted to run a game with more intra-group conflict. Apocalypse World is perfect for that sort of thing. I might still use the air combat system.
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| Pulp Covers |
Deep Time & Sky Islands
Some aircraft-heavy settings take a "transplanted era" approach. Take our world, at a time with an industrial (or near-industrial) technology level and mindset, and transplant it to a world with floating islands. The Warbirds RPG does this, but it has all has all the drawbacks of alternative history. Starting from scratch requires a complete world history (or, at least, enough of it for RPG purposes).
For now, picture a standard sky islands setting. Water below (way below), varying layers of floating islands above. Assume that humans evolved on a now-sunken island. Alternatively, this is an artificial world in space or virtual reality or something. Whatever conceit helps you sleep at night. It probably won't come up in the game, so why worry? And a source of atlantean/precursor tech might be useful.
Any fictional science-based prehistory has to account for millions of years where humans (or hominids) had fire, stone tools, and not much else. Perhaps a continent-sized island was stable for millions of years, then began to break up. Slowly at first, giving time for primitive maritime / aeronautical technology to develop, and then quickly. Without technology more advanced than a really good rock, flight (and therefore expansion and long-term survival) is not possible.
In the real world, dyed flax and thread turns up around 36,000 BC. So let's set 50,000 BC as the absolute lower limit for kite-building, which also corresponds with canoe-building and oceanic navigation.
The pressure to expand is constant. The family farm / pasture / cove / hunting ground can support a certain number of people. You're surplus. Or the local prospects offer no chance of the good life. The traditional response is to go to a nearby farm / pasture / etc. and either join their group or hit them until you've got their stuff. Sometimes both.
But on a sky island? If you want to move, you'll need more than a hollow log.
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| Juhyung Kang |
A hot air balloon?
Thin cloth is required, which needs a loom, and looms are time-intensive processes. It's difficult to fuse and seal skins and bladders, but it could be possible. Paper could work, but strong and thin paper needs a surprising amount of chemistry. Building a balloon could be a family or community effort, but it feels plausible once linen-type plant cloth is available. A balloon allows for tethered flights to a nearby island.
For untethered flights, steering is a problem. To steer, you either need to go faster than the wind (a powered aircraft) or slower (a sailing ship, a balloon with an anchor, a tethered kite). Without an external force, anything caught in the wind is going wherever the wind is going, and that might not be survivable. Control surfaces on a kite or glider let you turn gravity (via altitude loss) into that external force.
Kites and gliders?
Building a kite just requires skins and reeds. Tethering it requires strong, light, and thin string. Bowstring technology could be adapted to kite strings. I'm not sure if you could get away with sinew. The heavier the kite, the more wind you need to lift it, and therefore the stronger your cord needs to be, so thin material (such as silk and paper) will be more effective than leather or raw plant material.
Gliders are hard to test without risk of injury. You can spend years trying to smelt copper, weave baskets, or make fireproof clay pots without putting your life at risk. You can paddle in the shallows before testing your canoe on the open ocean. But there aren't many safe intermediate stages for a man-lifting kite or a glider.
In the real world, there was no incentive to develop gliders other than ambition and entertainment. There was always a way to get from "up here" to "over there" that was far safer. But in a sky islands setting, there's a strong and consistent incentive. If population pressure is the main driver of expansion, then there's also a source of test pilots willing to risk death.
Multi-person copper-age gliders seem feasible. Dangerous, but feasible. Moving from non-functional bird-imitating feathered frames to actual gliders just requires experience, not any modern scientific principles. Those help, but they're not strictly required. Think about how many millions of brain-hours were spent developing sailing technology, against the attempts of a few idle speculators in aeronautics. Textile technology is still critical. A hang glider isn't dugout canoe tech, but if you can build a crab claw sail, you can build a glider.
Prehistoric pilots also have the advantage of height. Assuming the maximum altitude for settlement is 15,000' (rounding down a bit), that gives a pilot a lot of room to regain control and search for updrafts.
What about trained birds?
Birds can, with great effort, lift things. A bald eagle can carry a salmon, but not elegantly, and not for any great distance. They don't have have a lot of excess capacity. A large extinct condor could lift (perhaps) 40lbs, with a lot of flapping and fuss. A bird capable of lifting a human and flying for 1,000m would be implausibly large... and hungry enough to see humans as a snack. It's difficult to train something that can casually snip off your head.
Could you train birds to fly in tandem? Maybe, but it seems implausible. Efforts to train them to carry coconuts have been unsuccessful. I think if you caught 50 geese and tied them together with rope and leather harnesses, all you'd have at the end of the day is a tangle of irate waterfowl.
Side Note: I suspect bird domestication would be heavily incentivized. Cormorant fishing could allow floating islands access to the bounty of the sea.
Scale and Terminal Velocity
Concerns over glider development and inter-island flights can be solved making humans very small (or making them Redwall-style mice.) Squirrels can (allegedly) survive a fall from any height (though you shouldn't test this at home), so squirrel-sized humans would have an easier time discovering flight. But shrinking the scale introduces some odd leaping / throwing effects that I don't want to deal with; a squirrel-sized human could leap ~60' straight up. Still, there'd probably be evolutionary pressure towards smaller people with strong cartilage.
Archaic Tech
Why does this matter? If the setting has biplanes, why put any thought into sky-galleys and gliders? Is it just for the montage at the start of the film? Well, not everyone has biplanes. The logical development of a technology, stage by stage, can give a GM a set of useful tools.
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| Julien Gauthier, Chromantic Studio |
Lifting The Sky Islands
Oolith is a bluish-grey element that is affected by a gravitational field in the opposite manner to conventional matter. It floats; everything else sinks. The effect increases with concentration (analogous to radioactive decay).
Side Note: I considered going full Greg Egan and making atomic weight correlate to an element's susceptibility to gravity. Group 6 elements would be neutral; Group 7 would be repelled. But I'm no Greg Egan, and it seemed like too much effort to work out all the ramifications. Special relativity (probably) works in this universe; general relativity is right out the window.
Oolith makes flying islands possible. It is usually found in one strata. Rocks below the strata are more easily weathered (since they're hanging), which slowly exposes the oolith. As the exposed oolith is eroded (reducing its concentration), the island sinks. The fragmented oolith falls to the core, where it is trapped and concentrated by geochemistry. If enough is concentrated in one place, it can break a chunk of semi-molten stone free, forming a new island. Geosophists believe the ancient continent [name] was broken up by an island rising below it.
The largest current islands are ~100,000km^2; the size of New Zealand's North Island, Iceland, Newfoundland, Cuba, or Ireland plus Wales. Small islands can be very small indeed. Any natural island under 50' square has a tendency to tumble and break apart, sending fragments sinking into the depths.
Experienced prospectors can identify oolith-bearing sands by watching them fall, or oolith-bearing minerals just by dropping a stone. Oolith is present in several minerals (with varying and confusing cultural names.) Crystaline oolith can form under certain conditions, but is rare and difficult to mine. Once a crystal is freed from its matrix, it tends to rise rapidly.
Oolith cannot be smelted. Ancient techniques relied on plants (see Luftbrush, below), crystals, or unusually pure deposits. Modern techniques use acid leaching to concentrate oolith.
Putting A Spin On Things
Gravity, in this setting, is analagous to electromagnetism. The world produces a strong, diffuse, and uneven gravitational field. Oolith has to move through the field to be repelled. This is not difficult; islands float and the field-producing core rotates below them.But if you take concentrated oolith and spin it, the repulsion effect increases. A stone that barely hovers can, if swung around a person's head, gradually provide lift. A primitive glider would be much more effective with one person steering and one person using a lift-generating whirligig with a crystal oolith core. This lift also acts as a stabilizing force (beyond merely gyroscopic effects). It takes more effort to move a spinning oolith than a stationary one.
Side Note: If the oolith is lifted (rather than generating some sort of antigravity field), then holding it is not a good idea. Think of it as a skyhook; the user would be lifting themselves, and any attached glider, just with their arms. Attaching the stone to a frame and using a bow drill makes a lot more sense. If a non-rotating stone provides a few pounds of lift, and only transforms energy when rotated, then a rotating stone's lift is equivalent to the lift a person could provide by gripping a skyhook or immobile rod. It's an efficient no-air-required propeller. This could turn an inefficient glider into an efficient one, or stop a terminal fall, but a purely human-powered aircraft would require the same engineering as in the real world.
Ancient sky-galleys used teams of rowers, with individual air-paddles or with banks connected into sinusoidal waves. Lift was provided by millstone-sized discs.
Longships were the first to use vastly more efficient propellers. Rowers were placed inside an aerodynamic wooden hull, facing each other, and gripping (later pedalling) one or more crankshafts. The shafts were coated or embedded with oolith and connected to a propeller. The same effort both lifted the craft (via oolith effects and external wings) and propelled it forward. Longships could cross vast distances efficiently, especially if aided by hot air balloons and sails when moving with the wind.
Gearing and springs allowed for larger and more complex aircraft, sometimes using different oolith arrangements to manoeuvre. Steam power enabled very large vessels, but demanded correspondingly vast expenditures of oolith. But any aircraft relying on oolith was ponderous, and oolith's rarity encouraged the development of "unlofted" aircraft.
The properties of liquid or gaseous solutions of oolith are not well understood. This is good mad pulp science tech. If this setting has a space program, implosion of an oolith crystal will probably be involved.
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| Jourdan Tuffan |
Luftbrush
If a thing exists, life will try to use it to its advantage. On the other hand, I'm not aware of any species (other than humans) that deliberately separates radioactive isotopes or navigates using radio waves.
Bioaccumulation of oolith is possible. Plants sometimes leach toxic metals as a defense. The seeds of the Luftbrush plant contain a tiny grain of oolith, and evolved to spin as they fly, generating extra lift and allowing for greater dispersal. Luftbrush seeds were gathered and carefully burned, and the ashes sifted and concentrated (in inverted clay pots, as the oolith tended to rise). The concentrated oolith could be trapped in clay or glass.
Ooltih is mildly toxic, but some cultures ritually ingest it, in the hopes of preventing fatal falls. There's no evidence to suggest that it accumulates in human tissues.
It's difficult to justify sky whales in this setting. I don't want to go fully magical. On the other hand, giant flying flock-of-bird-devouring dive-bombing whales full of valuable flotation oil seem like fun.
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| Orion's Arm |
Floating Geography
Because I can't leave well enough alone, this world is a torus. Gravity is not provided by centripedal force (like a ringworld), mass (like a hypothetical toroidal planet). It's provided by the rotation of specific elements; a large amount in the sun, a smaller amount on a planet's core. The world is therefore thinner than one might expect; a hoop instead of a donut, but not a ring.
The world wobbles relative to the sun, so it has seasons. If its axis of rotation is slightly offset from its orbit, it would have an equator along the outer rim, two temperate zones above and below the equator, two ice caps on the upper and lower surface of the ring, and a colder but non-frozen zone around the hole. Here's an article that covers all this and more.
Wind is a problem. Topologists claim you can comb a hairy donut, but you can't comb hairy balls. They'd know, I suppose. On a sphere, wind has a built-in source of chaos. The muddle at the poles introduces instability, which wobbles down the whole system, creating little vorticies and patterns. On a torus, winds could build and build without disturbance. Thermal cells, a hot core, and planetary oscillations could help. There might be a diagonal / corkscrew element too, from the torus' rotation. The absence of large land masses (other than the ice caps on the upper and lower surface of the torus) would make the winds relatively uniform, so ocean surface temperatures would be crucial. The seas would make the southern ocean look like a swimming pool.
Inhabitants on the outer surface, between the two ice caps, might not know their world is a torus. Sure, at sea, one horizon is closer than the other, but the chances of this being noticed seem low. Determining a torus world's latitudinal size (thickness) should be possible by ancient methods. Longitude (wideness) would be trickier. If a small island was known to circle the world on a predictable cycle, then estimates of its overland speed (over a large island) could lead people to conclude that the world is much wider than it is tall.
This creates an isolated "new world" on the inner surface of the hole, across the polar ice caps, which is ideal for RPG purposes. Mad polar explorers, struggling for months against arctic winds and blinding ice towards the north pole, only to discover that there's more world - a lot more world - on the other side.
Planetary Structure
- Mantle. Around 10,000' below sea level, with occasional deeper pockets. A braided tangle of rock, with a molten core.
- World-Sea. Occasional oil seeps, volcanic gas pockets, and other hazards. Large underwater islands, separated from the core but unable to rise above the water.
- Surface Islands. Islands able to rise to the surface of the water, but either unable to rise further (or slowly rising). Fishing, oceanic travel, and warmer temperatures makes these islands more appealing than sky islands.
- Sky Islands. Floating chunks of rock. Sometimes they become gravitationally coupled, floating in groups or chains. Newly risen islands often have a thick layer of nutrient-rich silt. Lichen, fungi, and windborne seeds arrive shortly. Birds transport plants and small animals. Trees appear within a decade.
Purely for visual appeal, I'm increasing atmospheric pressure to ~2atm at sea level. This means water boils at 120oC, which is annoying but not the end of the world. Nitrogen narcosis might set in during rapid altitude changes, but human biology can cope. Maximum habitable islands are at ~22,000'. This might help even out global temperature variations, but I this isn't the kind of setting where climate modelling is required. We're in the weeds already.
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| Jose Ramirez, Chromantic Studio |
How Many Mustard Seeds To Move One Mountain?
I know I said this was a low-effort setting, but sometimes, a bit of math is required. Take a sky island 1km long by 1km wide by 0.2km deep. Density of 2,500 kg/m^3. Mass of 5x10^11kg.
Assume the island is stationary and (for convenience) at 1 atmosphere of pressure. A horizontal wind of 100km/hour (27.7m/s) striking one face of the island for 24 hours. How fast is the island moving after 24 hours? How far has it moved?
Let's start off with a back-of-the-envelope high school physics dragless system.
Area of face (A): 2x10^5 m^2
Dynamic pressure (ρd): 470 pascals.
Wind Force (Fw) = pdA = 9.8x10^7 N
Mass (m) = 5x10^11kg
Acceleration (a) = Fw / m = 0.000196 m/s^2
t = 1 hour = 86,400 seconds
Displacement = 1/2at^2 = 7.3x10^5 meters = 731 km.
Final velocity = at = 16.9 m/s = 60 km/h.
This is wrong for many reasons. For example, the force isn't constant; as the island accelerates, the relative wind speed drops. But it is a useful sanity check. Sky islands move at a noticeable but not alarming rate (if aerodynamic drag and magical oolith drag are included). You could do better calculations to get a more accurate number, but that's not the point. The point is that, in a worst-case scenario, a farm-sized island won't end up circling the globe or flying into space. You could just as easily say that small sky islands move at the average local wind speed, matching changes in wind speed more slowly as their mass increases. A Newfoundland-sized 2km tall sky island has a mass on the order of 5x10^20 kg, while its wind-facing area is around 5x10^8 m^2. By the same fuzzy math, 24 hours of 100kph wind would move that island a little over 1m. Not worth worrying about.
Vertical travel is more difficult to calculate, since it's based on a fictional material. An island rising from the core would, upon reaching the surface, briefly accelerate its rise as the ground/sea water drains from its rocks. The rise would slow as plants colonize the island, absorbing atmospheric CO2. This could, possibly, lead an island to sink again after a few decades in the air. This cycling might be how hydrocarbons form; a heavily vegetated island that suddenly loses its ooltih layer and falls could be compressed, then uplifted later.
Just putting a sail on a sky island wouldn't allow it to be steered. It'd still move with the wind. But, since oolith is an external force, using aerofoils and sails to spin the island (increasing the lifting force of oolith) could increase its height. That lifting force could be transformed into horizontal motion, but it'd be a fairly intense engineering project. Windmills connected to propellers could also work, but not quickly.
Timekeeping On A Hoop
The calendar is a mess. On a large and stable island, fixed stars and seasonal variations are predictable. On a small island, which can wander hundreds of kilometers per year, seasons are probably a matter of guesswork and hope. If an island sticks to a latitude band, then its seasons are predictable (though offset from a stationary island). Celestial navigation should let people determine their latitude, but determining longitude, without fixed reference points, would be even more difficult.
Does any of this matter for RPG purposes? Maybe, but probably not. Still, thinking about this sort of thing can lead to gameable scenarios. Large islands have a monopoly on (and possibly an obsession with) mathematical calendars. Radio beacons would revolutionize long-distance navigation.
Life Aloft
In a setting where continental drift happens over the weekend, large terrestrial animals might be at a disadvantage. There are probably some semi-aquatic creatures, able to climb onto land temporarily: Crocodiles, Ambulocetus, that sort of thing. Anything that can climb quickly and eat moss might survive. Deer, goats, guinea pigs, capybara. Humans could transport them from island to island. A domesticated animal that fits under one arm would be worth hauling in a glider. Flying animals have an enormous advantage. Draft animals are probably rare; the incentives to develop gearing and mechanisms for oolith rotation make wind and water power available fairly early.
Water is probably a major limiting factor. Large islands at sea level could support groundwater and lakes, the sea water pressure would prevent the water from escaping. Flying islands could trap some water, but I'd expect most of it would dribble out. Collecting and storing rainwater could influence the architecture. Boltholes and safety ropes would be useful, and probably culturally coded, on small islands.
Island Speciation
In this setting, humanity spread onto sky islands during the neolithic era (give or take). This isn't enough time for truly wild mutations to take root. The pressures of flight would probably lead to smaller people with quick-healing ankles, but gills, patagiums, etc. are unlikely. On the other hand, if there's an inner ring crossover (see Floating Geography, above), an entirely separate hominid lineage could split off earlier. And it's an RPG setting; if you're going full fantasy, you can add orcs and goblins and what-not with some justification.
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| Pulp Covers |
Useful Media
But we have seen and heard of many people overcome with so much foolishness, made crazy by so much stupidity, that they believe and say that there is a certain region, which is called Magonia, from which ships come in the clouds. In these ships the crops that fell because of hail and were lost in storms are carried back into that region; evidently these aerial sailors make a payment to the storm-makers, and take the grain and other crops. Among those so blinded with profound stupidity that they believe these things could happen we have seen many people in a kind of meeting, exhibiting four captives, three men and one woman, as if they had fallen from these very ships. As I have said, they exhibited these four, who had been chained up for some days, with such a meeting finally assembling in our presence, as if these captives ought to be stoned. But when truth had prevailed, however, after much argument, the people who had exhibited the captives, in accordance with the prophecy (Jeremiah 2:26) "were confounded … as the thief is confounded when he is taken."
-Agobard of Lyons, On Hail and Thunder, 9th century.
I've already listed a few of the obvious examples in this post. Here are some more obscure ones.
The Pirates of 1920 (1911)
In the far future of 1920, airships will be used to stage daring robberies. May have canonized the standard sky pirate uniform (coat with two rows of buttons, leather cap, goggles, belt and holster.) Also predicted the techniques used in (arguably) the first case of actual air piracy.
The Phantom (1996)
A fairly awful film with an excellent villain. Just a truly crazy Hurst / Hughes type, drawing from the same well as Cave Johnson. A pulp lunatic surrounded by people from a different genre. It's only on this list because of some minor air piracy (done by actual central casting pirates) and general pulp tropes.
The Three Musketeers (2011)
A star-studded cast, expensive costumes, shoots on location, a familiar plot with an alt/pseudo-history twist. And yet, it's (rightly) forgotten. Why? I think it's the lack of heart. There's a sense that every scene is recycled, every line of dialogue written by a committee. You've seen every part of this film before, but better.
Skyland (2005-2007)
A Canadian children's TV show from the early motion capture CGI era. Is it good? No.The Curse of Count Zeppelin fell upon them, and the result is profoundly mediocre. It's got sky islands, but it is fundamentally a sci-fi show. Specifically, it's a Star Wars show with the serial numbers filed off... and not that well filed off either. Still, if you needed inspiration for a Star Wars game, it... exists.
Last Exile (2003, 2011)
At last, something good. For some people, this is probably foundational dieselpunk media, but it might be new to you. The promotional materials have an odd focus on teenagers in sundresses, but next to none of this appears in the series (thankfully). It's just a solid bit of worldbuilding, political drama, and interesting visuals.
Just Imagine (1930)
No sky pirates, but a good retro-future yarn. 1930 envisions 1980, watched in 2030 (rounding up). Perhaps this confirms that the Curse of Count Zeppelin doesn't rely on tropes from the pulp era failing to resonate with modern audiences. The problem is deeper. Just Imagine predicts video calls, hair dryers, and future shock. It has some of the best city sets outside of Metropolis, and some of the most blatant hollywood rhubarbs outside of radio comedy (18:24).
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| Attila Varga |
Final Notes
Normally, I'd consider running a pulp game in a pulp-inspired (or at least pulp-compatible) system. But the more I think about a Sky Pirates game, the more I'm inclined to punk over pulp. Punk needs risk and stakes, not cinematic competence.
Spending time and effort on the details of a setting is not required, but it can hep a GM build a mental toolkit. Now that I've done the research (if you can call it that), I can visualize how far sky islands are from the sea, how a fictional technology might develop, and some of the problems a sky islands civilization might encounter.
If you have any thoughts on this post, feel free to leave a comment.
