Flat World design

Umbran

Mod Squad
Staff member
I mean okay, but I know he figured out the sun and the moon by having light move at an incredibly slow speed. or something like that. the point is he figured some stuff out, even if it was hand wavey.
It seems more like he wrote some stuff that sounded cool , but then found he'd written himself into a corner and made up more stuff until he foudn a way out.

He made it so that Discworld's sun and moon were a pair of objects orbiting Great A'Tuin. But, he also described a normal sunrise, with day/night terminator. But on a flat disc, the terminator moves along at the speed of light - the entire disc would see the sun nigh instantaneously, so he wrote some florid stuff about the speed of light... which he then ignores for the rest of the work, which is good, because he'd also have issues with people looking at things at any appreciable distance. He wrote until he cold sweep the issue he'd created under the metaphorical rug.

And that's fine. For a fantasy series there's no problem with that. But it then follows - you don't actually have to figure anything out - unless it is going to be part of the plot the characters deal with, you don't need to specify how things work!
 

lordabdul

Explorer
I don't think you can get away from any hand-wavey explanation for a flat world... I mean, that's why flat worlds don't exist :) Discworld and Glorantha are great examples of flat worlds. The first one explains it with funny bits and vague stuff, while the second explains it all with deeply complex mythology (and, therefore, since the world is real, the mythology and the gods are real too).

I think that before you go and try to design a flat world, you would have to figure out the tone. Where Discworld is whismsical and Glorantha is mythological, what would your world be? If you want it to be mysterious, just don't explain much. If you want it to be pseudo scientific, go crazy with pseudo scientific explanations but then make the setting similarly pseudo scientific, otherwise it's just a useless thought exercise[1] that doesn't have any consequence on the game itself. So maybe it shouldn't be a straightforward medieval fantasy setting... it might be an "Age of Philosophers" setting where the countries are mostly governed by scholars and researchers and universities and stuff... and these organizations and people need adventurers to explore the world's limits to prove/disprove their theories, retrieve rare items, and do some "corporate" espionage or something. Imagine the PCs coming back after an insanely difficult 6 months-long journey: "so we went through the mountains at the edge of the world, but we ended up in Larkvelia, which is supposed to be on the other side", and their patron scholar goes "ah shit, well, so much for this theory (throws away papers)... ok, well, I've got this other theory, but how long can you hold your breath?".


[1]: To be clear I'm all for useless thought exercises, they're fun too! But they're kinda what created the flat earthers in the first place :)
 

Tonguez

Adventurer
I mean okay, but I know he figured out the sun and the moon by having light move at an incredibly slow speed. or something like that. the point is he figured some stuff out, even if it was hand wavey.
That was pretty much a joke observation too

light on Discworld moves slowly due to the effects of its high magic field, a person at the top of a very high mountain would be able to physically watch light from the sun "move" across the surface of the Disc . It’s takes light about 2 hours to travel from AnkhMorpork to Quirm (which is estimated at 600mph, although that’s never stated by Pratchett). However no matter how fast Light moves, Darkness always gets there first
 
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You could always take a concept from the modern flat earth movement, and have the world ringed with a gigantic wall of ice that surrounds the edge. To keep fliers from going over the wall, have the air thin out before the top.
 

Gilladian

Adventurer
Giving the ocean a supervolcano at its center would explain how the ocean is heated to steam which rises to the crystal dome where the water evaporates to form rain. Make it like a regular geyser that blast water into the sky, thus accounting for both clouds and tides. This way you dont need the hot spot in the sky (you’ve got a hot spot in the ocean instead)

Seasons could be due to rotation of the hot water from the source flowing in a constant current around the disc. The head of the flow is hottest (summer) but dissapates as it goes around leaving a cold tail (winter). Winds blowing inland and flow into bays etc cause regional weather effects but there would be a constant swell pattern and rim-wide trade wind too which would make navigation easy with the current, but difficult against it.


Addendum: Have the Geyser blast cause the Crystal dome to glow brightly and then dim, causing the same day and night cycle to occur simultaneously across the disc:)


Pratchett essentially handwaved it as narrativium, however

“Since the disc's tiny orbiting sunlet maintains a fixed orbit while the majestic disc turns slowly beneath it, it will be readily deduced that a disc year consists of not four but eight seasons. The summers are those times when the sun rises or sets at the nearest point on the Rim, the winters those occasions when it rises or sets at a point around ninety degrees along the circumference."
—The Colour of Magic, footnotes, page 5
Oh, wow, this is good stuff! Thank you! If I get a chance over the weekend I will write up my first draft on this world.
 

Gilladian

Adventurer
I don't think you can get away from any hand-wavey explanation for a flat world... I mean, that's why flat worlds don't exist :) Discworld and Glorantha are great examples of flat worlds. The first one explains it with funny bits and vague stuff, while the second explains it all with deeply complex mythology (and, therefore, since the world is real, the mythology and the gods are real too).

I think that before you go and try to design a flat world, you would have to figure out the tone. Where Discworld is whismsical and Glorantha is mythological, what would your world be? If you want it to be mysterious, just don't explain much. If you want it to be pseudo scientific, go crazy with pseudo scientific explanations but then make the setting similarly pseudo scientific, otherwise it's just a useless thought exercise[1] that doesn't have any consequence on the game itself. So maybe it shouldn't be a straightforward medieval fantasy setting... it might be an "Age of Philosophers" setting where the countries are mostly governed by scholars and researchers and universities and stuff... and these organizations and people need adventurers to explore the world's limits to prove/disprove their theories, retrieve rare items, and do some "corporate" espionage or something. Imagine the PCs coming back after an insanely difficult 6 months-long journey: "so we went through the mountains at the edge of the world, but we ended up in Larkvelia, which is supposed to be on the other side", and their patron scholar goes "ah shit, well, so much for this theory (throws away papers)... ok, well, I've got this other theory, but how long can you hold your breath?".


[1]: To be clear I'm all for useless thought exercises, they're fun too! But they're kinda what created the flat earthers in the first place :)
Ooooh, steampunk world! I haven’t ever set up one like that, and it could be really fun!
 

Richards

Adventurer
And if you have a curved "lens" above your flat world with a source of light above it (the sun or maybe even just the stars), the lens could be focusing the light (like a magnifying glass) at a point directly below it, possibly tying in to the heat of the supervolcano mentioned earlier....

Johnathan
 

Gilladian

Adventurer
Here is what I've jotted down so far, if anyone is interested:

My Flat World

This world is a flat,round disc. It is the ONLY thing in its universe. There is no "outside", only what exists as described here.

The world is about 2000 miles across. It is about 4 miles thick. The surface area of the world is "normal breathable earthlike terrain". It is ringed by mountains, capped by an impenetrable ceiling which curves slightly up from the mountain-tops (which are all flattened off, neatly), and is apparently impenetrable. The tallest of the mountains, at the edge, are about 2 miles (10,800 feet) high. The "beneath"of the world is a layer of rock and earth and water. It is also about 2 miles thick. Digging "down" through this results in hitting an impenetrable barrier. In fact, if anyone ever penetrated this barrier, they would find themeselves falling from the sky to the earth below.

In the same way, if anyone ever tunnels through one side of a mountain on the edge of the world, they would find themselves emerging from the mountain on the opposite side of the world.

The surface world has a large lake/sea (saltwater) in the center. It is about 5-700 miles across. At the center is a volcano with a small island around it. This volcano is know as the Light of the World. Each morning, it "erupts", shooting a massive blast of hot, steaming water at the sky. Where it hits the sky it creates a wave of light. This light spreads across the sky at an even pace, creating "dawn". The eruption lasts about 9 hours, and then slowly ceases. About three hours after it stops, the light of day fades away, bringing night. It takes about one hour for dawn to spread, and about the same amount of time for night to creep out, or for day to fade away. People in this world don't speak of sunrise or sunset; instead they speak of dawn, or lightspread, and dusk or lightfade.

There are two "other" planes of existence. One is the feywild/shadowfell sort of world - it is very similar to the prime world, but wilder and more intense. There is no true lightspread or day here; instead dawn creeps out as a rosy glow, and fades away into purple twilight that never truly darkens completely. The second is an elemental plane, where earth, fire, water and air are far more primal, separated, and alive. This world is incredibly harsh and dangerous to the humanoid races, and few ever go there. Day and Night are far more pronounced there; daytime is brilliantly hot and bright, while night plunges into blackness, with only the fiery elementals visible.

The prime world is dominated by nine draconic rulers. The Light of the World is home to an eight-headed dragon/hydra type being named (). He/she/it is the parent of eight offspring dragons, who have divided the world between them. These eight beings are neither good nor evil, nor are they "color-coded" like traditional dragons. All are extremely powerful rulers with breath weapons, spell-casting, and other abilities. They do have more "normal" dragon subrulers who are their descendants who are called Dukes/Duchesses, Princes and Princesses and Marcher/Marchesses. Beneath them are the human, elven, dwarven and halfling peoples, who are ruled by the dragons. There are also wilder regions where orcs, hobgoblins, and other creatures still dwell, each ruled by one of the more unruly dragons. No humans quite know why the dragon rulers find it necessary to retain these troublesome groups, but they have learned that it is always necessary to keep up their defenses, for sooner or later, they will boil over outof their lands and attempt to swarm the more peacable countries.
 

MNblockhead

A Title Much Cooler Than Anything on the Old Site
The world is a massive and incredibly ancient space ship. A kind of interstellar ark made on a massive scale. The "gods" are the original builders. Instead of the trope of lost knowledge and technical degeneracy, perhaps the original builders created the ark to save the denizens of one or more dying planets. Maybe something caused the original builder to lose contact with the ark. Or maybe they occasionally check in (i.e. an explanation for gods).

You could probably handwave gravity, light cycles, etc. with the answer "incredibly advanced technology".
 

Bilharzia

Villager
Glorantha is a 'flat world', technically a lozenge. It doesn't follow some of your assumptions though - so it certainly does have a moon, the 'sun' (a god) who travels from the upper world into the underworld and so on. It's probably worth a read if you're designing such a world.
 

Gilladian

Adventurer
The stars: there are sparkling spots embedded in the sky. They only show up at night, and seem to have their own internal light source. Over hundreds of years, it has been observed that these stars move gradually outward, towards the rim of the world. Otherwise, the night sky does not change. (They are magic gems and the sky disc grows continuously, is pushed down behind the mountains, and to the underside of the world, where it is pulled back to the center and pushed out again by the Light of the World. )

Moon? Could be a physical object that moves around? Or not exist. Or be a fixed giant gem That brightens and dims internally for no known reason. There could be several of them, I guess...

Seasons? Could be caused specifically by the dragon god at the heart of the world. What if each quarter of the year there was a different dragon-ruler consort, which causes the season to change. Or what other idea?
 

Nytmare

Adventurer
What do people say as directions in this world? Is there one particularly prominent (and maybe iron-rich and thus magnetic) mountain that people consider 'north'?
I don't know if it's directions come up eventually, but in Diskworld they use hubward if you're heading towards the center, rimward if you're heading towards the edge, and turnwise and widdershins for travelling in the direction of the world's spin or against.
 

chrisshorb

Everything's Fine
I run Ravnica as a flat world, about 160 miles in diameter. The world is bounded by unbreakable walls. There's a "sun" that moves across the dome every 10 hours, followed by 10 hours of night (although the amount of magical light generated by the city means it's never really "dark").

There's water in caverns underneath most of the city, about a mile or two miles deep. At the bottom is more of the same unbreakable material as the walls.

Part of the campaign mystery is finding out what's underneath the "bottom". If/when they get there, they'll find a pristine, untouched realm divided into mountains, plains, islands, swamp, and forest. It's basically a reservoir of mana, which is recycled by the "sun" (which actually just collects ambient mana) every daily cycle.
Stealing.
 

Legatus_Legionis

< BLAH HA Ha ha >
I always found it extremely rare that a group would travel far and wide enough to make a "around the globe" campaign.

Any "edge of the world" is so far away/so inhospitable no group could every travel to it.

Or....

You can have it like the film "Dark City" or Judge Dredd's Mega-City style. Most people know their world ends at the big wall, and what is beyond is death. Curiosity of what is beyond is not something most think about.

And if you end up wanting your players to adventure in a different setting, you can have them discover a tunnel/passage to lead them from one "Dome" to another "Dome". Just like the experiment of "Earth2". Each dome is its own ecosystems.

Or climbing up a mountain side, to were the cloud cover gets thick, one can climb between rock croppings to discover they have climbed into a ravine they are at the bottom of. And vice versa. Just like how they explain the planes of existence.
 

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