How long to fill the demiplane
Sep. 10th, 2023 09:35 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
beccaelizabethI was thinking the Stargate evacuation problem
(how many people could you really fit through the Stargate in one day)(my previous answer was something like about as many as travel through Heathrow Airport, but I don't remember my math, just it has some obvious implications for limits on interplanetary travel, especially in an emergency)
But this time I was thinking demiplanes. Like as a level up from Magnificent Mansions, you can create and Permanency your own demiplane, but it's going to be an expensive way to make a safe zone. Should still be safe even if antimatter though, or negative energy, it just might get a teensy difficult to get out again. But by the time you can Create Demiplane, even Lesser, you have some impressive options on travel.
It's possible to create a permanent Portal with Greater Demiplane, but that would have some safety implications, I'd think. Have to look up Gate, like, can you accidentally blast yourself with conditions on the other side of the gate.
I tried googling stuff like how many people can walk through a door in a day or how long does it take to walk through a door, but once walk through a door is included all the answers are about that thing where you forget what you were doing when you walk through a door. Google has gone terrible useless now.
But you just need to know person speed and count them walking past a line on the floor and then figure out how many of them walk side by side and the you get persons per minute.
Which is a lot of wiggly variables in real life but in Pathfinder you've got a listed speed, usually 30 feet per round for a medium humanoid, and you know they need one five foot square each. That works out at 12 people per six seconds through a five foot door, or 24 through a ten foot one. Or rather, in single file, six people at base speed if they want to be able to fight as well as move, twelve if they're just moving, and 24 if they're just running. Without adding in heavy armour or heavy loads.
Maximum 480 people per minute through a 10 foot wide door, lots of ways to go slower, but also ways to pack tighter so *shrugs*.
Demiplane math, like most rpg things, reckons you'll be moving your party and your cohorts around at most. 480 people is like a large army. Actually lets look it up, army rules are in Ultimate Campaign... 500 is a Huge army so at just short of that it is Large.
It's going to take a lot of money and Many castings of this spell to Create a Permanency-ed demiplane big enough for 480 people to stand in. Getting people inside is less of a problem than having somewhere to stand.
Building big enough for a permanent human colony, like a demiplane designed as a generation ship, say to outlast Earthfall... oh that's expensive.
Actually no, at Greater Demiplane, less than I thought...
so okay, three forms of Demiplane, Lesser, Demiplane and Greater. 7th 8th and 9th level for a wizard.
Lesser gets you up to 3 10ft cubes per level. Cubes matters, if you want more ceiling height or intend to make yourself a Large of Huge being at any point, but for now lets math it like 10ft tall is all we need. 4 people per cube have enough space on a normal combat map. Not enough to lie down in yet, but, a wizard casting a 7th level spell is at least level... 13. 15 for 8th, 17th for 9th.
13*3 of 10ft cubes, *4 for people who could stand in them. 39 cubes, 156 people. 3 and a bit castings to make floor space for one minute of people through a 10 foot door. Each casting takes 2 hours, so in one 8 hour day you could make a 156 cube demiplane that sticks around for 13 days. Make it Permanent with 4 castings each costing 17,500gp. Permanency casting time says two rounds, on an 8 hour day that's a rounding error, you'd finish it in a minute.
Create Demiplane as an 8th level spell makes up to 10 ten foot cubes per level, casting time 4 hours, so 150 cubes per casting with room for 600 people to stand. Permanency costs 20,000gp. And you get some big advantages over Lesser demiplanes, like you dont got to bring all the contents by hand, a full demiplane can have Structure and be Bountiful. A Structure can be all kinds of things, it says "This option exists so you can pick a theme for your plane without having to worry about the small details of determining what spells you need for every hill, hole, wall, floor, and corner." Because Lesser only gets you "flat and featureless, such as an earth, stone, water, or wood floor." It's also filled with air or water as per your choice. "The 'walls' and 'ceiling' of the plane may appear like solid earth, stone, wood, or water, or they may end in mist, a featureless void, or similar unreal-looking border." It's like a temperate spring day and you can decide the light level but it stays that way for as long as the plane exists. That's Lesser. With a full Demiplane you can have structures and seasons and a day and night cycle, on your chosen clock. Always winter with 4 hour days is doable. Not wise, but doable.
It takes a lot of castings to get all the features, but, Bountiful means one 10foot cube can support one Medium creature indefinitely, enough food and water and so forth.
... if you want to live in a garden you could maximise Bountiful but personally I would want a Bountiful side as well as a Structure side.
Greater Create Demiplane gives you all the bells and whistles, all the settings for energy, magic, and time. Plus you can make it morphic and bend it to your will. 6 hour casting time, but up to 20 ten foot cubes per level, so at 17th level you get 340 cubes at once, up to 400 at 20th. That's a lot of cubes to work with, but you'd still fill them in a very few minutes. Permanency costs 22,500gp.
39 cubes for 17500 is not as good a deal as 340 for 22500.
about 450/cube vs about 66/cube. Not bad, you can imagine charging people 66 for life support and 66 per cube for living space, to make a bolt hole.
Getting in and out is either a Greater Demiplane's Portal or an individual problem.
"The gate itself is a circular hoop or disk from 5 to 20 feet in diameter (caster's choice) oriented in the direction you desire when it comes into existence (typically vertical and facing you)." And if you cast it it is only open for one round per level, so maximum two minutes. Not many castings per day, if you're planning an evacuation you want scrolls I guess.
That permanent connection is looking cheap at 22500.
Don't reckon a 20ft diameter circle is a 20 foot wide door even if you drop it down to halfway in the ground, if you even can. Stargate problem. You can fit the 10ft cube through the 20ft circle easies, but the edges get trickier.
Aaand the weird specifics of the RPG simple this up a lot: we know the template for a 10ft diameter circle made of 5 foot squares. If your ramp goes up five feet high then you have four five foot squares to walk through that are each 10 feet tall if you've oriented the circle that way. So not a 10 foot door, an actual 20 foot one, or two lanes of traffic.
That's up to 960 medium average speed people per minute, or 1,920 running people per casting.
Well that's going to add up.
And if the goal is 4 sets of ten thousand people like the colony ship math... Well you'd need six gates per 10K city to get everyone in with a small margin. Not a one caster day job but like a weekend each maybe.
I'm thinking of trying to evacuate an Earth ahead of the Crisis, as you do.
I'm thinking there would be one permanent portal and a handful of Gate spells to get everyone out, and very little time to prepare.
Speedsters could use the permanent portal in both directions but you'd have to pick your places to evac others from.
It is still going to be so much quicker to fill than to build, and you'd need the money up front to pin each new section down with Permanency. If you make it Bountiful for everyone you plan to house and then bring a LOT of money in with you then you have time. Structure on its own is going to run out of life support. You're probably casting Demiplane a lot. 4 hours for 150 to 200 cubes. You can Bountiful 170 cubes when you can Greater Demiplane twice that. So six hours for Greater the 8 hours for Demiplane and then sleep. Well probably eater after Greater and between castings as well. Busy long day. And that gets you full life support on one Greater demiplane per day.
Ten thousand cubes at 200 per day is 50 days without a day off. And you just have a garden. A stupendously expensive extraplanar garden.
... I'm not saying Eden, but it makes a good story. Stay in the garden while someone Creates literally everything else...
So this isnt a particularly productive set of game math but taking a thought for a run is fun.
(how many people could you really fit through the Stargate in one day)(my previous answer was something like about as many as travel through Heathrow Airport, but I don't remember my math, just it has some obvious implications for limits on interplanetary travel, especially in an emergency)
But this time I was thinking demiplanes. Like as a level up from Magnificent Mansions, you can create and Permanency your own demiplane, but it's going to be an expensive way to make a safe zone. Should still be safe even if antimatter though, or negative energy, it just might get a teensy difficult to get out again. But by the time you can Create Demiplane, even Lesser, you have some impressive options on travel.
It's possible to create a permanent Portal with Greater Demiplane, but that would have some safety implications, I'd think. Have to look up Gate, like, can you accidentally blast yourself with conditions on the other side of the gate.
I tried googling stuff like how many people can walk through a door in a day or how long does it take to walk through a door, but once walk through a door is included all the answers are about that thing where you forget what you were doing when you walk through a door. Google has gone terrible useless now.
But you just need to know person speed and count them walking past a line on the floor and then figure out how many of them walk side by side and the you get persons per minute.
Which is a lot of wiggly variables in real life but in Pathfinder you've got a listed speed, usually 30 feet per round for a medium humanoid, and you know they need one five foot square each. That works out at 12 people per six seconds through a five foot door, or 24 through a ten foot one. Or rather, in single file, six people at base speed if they want to be able to fight as well as move, twelve if they're just moving, and 24 if they're just running. Without adding in heavy armour or heavy loads.
Maximum 480 people per minute through a 10 foot wide door, lots of ways to go slower, but also ways to pack tighter so *shrugs*.
Demiplane math, like most rpg things, reckons you'll be moving your party and your cohorts around at most. 480 people is like a large army. Actually lets look it up, army rules are in Ultimate Campaign... 500 is a Huge army so at just short of that it is Large.
It's going to take a lot of money and Many castings of this spell to Create a Permanency-ed demiplane big enough for 480 people to stand in. Getting people inside is less of a problem than having somewhere to stand.
Building big enough for a permanent human colony, like a demiplane designed as a generation ship, say to outlast Earthfall... oh that's expensive.
Actually no, at Greater Demiplane, less than I thought...
so okay, three forms of Demiplane, Lesser, Demiplane and Greater. 7th 8th and 9th level for a wizard.
Lesser gets you up to 3 10ft cubes per level. Cubes matters, if you want more ceiling height or intend to make yourself a Large of Huge being at any point, but for now lets math it like 10ft tall is all we need. 4 people per cube have enough space on a normal combat map. Not enough to lie down in yet, but, a wizard casting a 7th level spell is at least level... 13. 15 for 8th, 17th for 9th.
13*3 of 10ft cubes, *4 for people who could stand in them. 39 cubes, 156 people. 3 and a bit castings to make floor space for one minute of people through a 10 foot door. Each casting takes 2 hours, so in one 8 hour day you could make a 156 cube demiplane that sticks around for 13 days. Make it Permanent with 4 castings each costing 17,500gp. Permanency casting time says two rounds, on an 8 hour day that's a rounding error, you'd finish it in a minute.
Create Demiplane as an 8th level spell makes up to 10 ten foot cubes per level, casting time 4 hours, so 150 cubes per casting with room for 600 people to stand. Permanency costs 20,000gp. And you get some big advantages over Lesser demiplanes, like you dont got to bring all the contents by hand, a full demiplane can have Structure and be Bountiful. A Structure can be all kinds of things, it says "This option exists so you can pick a theme for your plane without having to worry about the small details of determining what spells you need for every hill, hole, wall, floor, and corner." Because Lesser only gets you "flat and featureless, such as an earth, stone, water, or wood floor." It's also filled with air or water as per your choice. "The 'walls' and 'ceiling' of the plane may appear like solid earth, stone, wood, or water, or they may end in mist, a featureless void, or similar unreal-looking border." It's like a temperate spring day and you can decide the light level but it stays that way for as long as the plane exists. That's Lesser. With a full Demiplane you can have structures and seasons and a day and night cycle, on your chosen clock. Always winter with 4 hour days is doable. Not wise, but doable.
It takes a lot of castings to get all the features, but, Bountiful means one 10foot cube can support one Medium creature indefinitely, enough food and water and so forth.
... if you want to live in a garden you could maximise Bountiful but personally I would want a Bountiful side as well as a Structure side.
Greater Create Demiplane gives you all the bells and whistles, all the settings for energy, magic, and time. Plus you can make it morphic and bend it to your will. 6 hour casting time, but up to 20 ten foot cubes per level, so at 17th level you get 340 cubes at once, up to 400 at 20th. That's a lot of cubes to work with, but you'd still fill them in a very few minutes. Permanency costs 22,500gp.
39 cubes for 17500 is not as good a deal as 340 for 22500.
about 450/cube vs about 66/cube. Not bad, you can imagine charging people 66 for life support and 66 per cube for living space, to make a bolt hole.
Getting in and out is either a Greater Demiplane's Portal or an individual problem.
"The gate itself is a circular hoop or disk from 5 to 20 feet in diameter (caster's choice) oriented in the direction you desire when it comes into existence (typically vertical and facing you)." And if you cast it it is only open for one round per level, so maximum two minutes. Not many castings per day, if you're planning an evacuation you want scrolls I guess.
That permanent connection is looking cheap at 22500.
Don't reckon a 20ft diameter circle is a 20 foot wide door even if you drop it down to halfway in the ground, if you even can. Stargate problem. You can fit the 10ft cube through the 20ft circle easies, but the edges get trickier.
Aaand the weird specifics of the RPG simple this up a lot: we know the template for a 10ft diameter circle made of 5 foot squares. If your ramp goes up five feet high then you have four five foot squares to walk through that are each 10 feet tall if you've oriented the circle that way. So not a 10 foot door, an actual 20 foot one, or two lanes of traffic.
That's up to 960 medium average speed people per minute, or 1,920 running people per casting.
Well that's going to add up.
And if the goal is 4 sets of ten thousand people like the colony ship math... Well you'd need six gates per 10K city to get everyone in with a small margin. Not a one caster day job but like a weekend each maybe.
I'm thinking of trying to evacuate an Earth ahead of the Crisis, as you do.
I'm thinking there would be one permanent portal and a handful of Gate spells to get everyone out, and very little time to prepare.
Speedsters could use the permanent portal in both directions but you'd have to pick your places to evac others from.
It is still going to be so much quicker to fill than to build, and you'd need the money up front to pin each new section down with Permanency. If you make it Bountiful for everyone you plan to house and then bring a LOT of money in with you then you have time. Structure on its own is going to run out of life support. You're probably casting Demiplane a lot. 4 hours for 150 to 200 cubes. You can Bountiful 170 cubes when you can Greater Demiplane twice that. So six hours for Greater the 8 hours for Demiplane and then sleep. Well probably eater after Greater and between castings as well. Busy long day. And that gets you full life support on one Greater demiplane per day.
Ten thousand cubes at 200 per day is 50 days without a day off. And you just have a garden. A stupendously expensive extraplanar garden.
... I'm not saying Eden, but it makes a good story. Stay in the garden while someone Creates literally everything else...
So this isnt a particularly productive set of game math but taking a thought for a run is fun.