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beccaelizabethToday I learned a very little more about excel while trying to get it to calculate the area of several geometric forms, circle, pentagon, and pentagram.
Then I gave up and just copied across a bunch of numbers from a web page that would calculate it for me.
And then I gave up on that because ugh, hand copying, I don't even plan to use this stuff, I just wanted some vague idea of it.
The problem is that the cost of Pentagram is calculated by area in square feet, not area as in area effect spell. And the spell description says "The barrier is a star-shaped figure drawn on the floor or ground." The picture arguably shows the standard star in a circle, so, my assumption was the area in question was the circle, and I made a chart of circle areas to find costs. Simples. But! What if it actually meant a star shape? On account of that being what it actually says?
I have now seen the formula for calculating the area of a star shape, and it is... very maths.
Very.
But I copied a bunch of the answers down.
But I also tried a few pentagons, because one bright spark on a forum suggested only the central pentagon would really hold a demon. Also I more or less managed to put the formula for that into excel. probably. it got samelike answers anyways.
So these three understandings of a Pentagram spell get very different answers, and all of them are really very expensive, when you consider all it takes for an unmagical being to break the spell is a chalk mark or scuff. "If part of the pentagram is cut or erased, its power will be lost until the caster can rejoin the pentagram - all this requires is a piece of chalk and time (usually just a second) to draw the line." Okay, so, sounds like it doesn't need recasting, just redrawn? That makes a large investment of power more worthwhile. But if a demon actually breaks out of the pentagram it needs casting over again.
You can cast a ten square foot pentagram in ten seconds for ten fatigue. Nice. But not fast enough once battle is joined, and not resilient enough to feet.
But it's a fiddly pain, it not being clear, or giving any numbers.
Also, given you can use enchantment rules to make it, the inventive player is going to have all sorts of thoughts about portable versions, and the description just doesn't go there.
Spell Shield is a prereq for pentagram and protects against fewer things differently but does have a magic item listed. A spell shielding rug or area of floor costs 400 per yard of radius. Which is very different maths indeed from the cost per square foot of pentagram. Which you'd think could also be cast on a rug, and can certainly go on an area of floor.
I know magic is under no obligation to be logical, but rules certainly are, if they're going to be playable by fiddly clever people.
Really, they couldn't have given a single example with radius? *sigh*
ANYway, I got sidetracked with math and that was my afternoon.
Is a good thing I find this fun.
Then I gave up and just copied across a bunch of numbers from a web page that would calculate it for me.
And then I gave up on that because ugh, hand copying, I don't even plan to use this stuff, I just wanted some vague idea of it.
The problem is that the cost of Pentagram is calculated by area in square feet, not area as in area effect spell. And the spell description says "The barrier is a star-shaped figure drawn on the floor or ground." The picture arguably shows the standard star in a circle, so, my assumption was the area in question was the circle, and I made a chart of circle areas to find costs. Simples. But! What if it actually meant a star shape? On account of that being what it actually says?
I have now seen the formula for calculating the area of a star shape, and it is... very maths.
Very.
But I copied a bunch of the answers down.
But I also tried a few pentagons, because one bright spark on a forum suggested only the central pentagon would really hold a demon. Also I more or less managed to put the formula for that into excel. probably. it got samelike answers anyways.
So these three understandings of a Pentagram spell get very different answers, and all of them are really very expensive, when you consider all it takes for an unmagical being to break the spell is a chalk mark or scuff. "If part of the pentagram is cut or erased, its power will be lost until the caster can rejoin the pentagram - all this requires is a piece of chalk and time (usually just a second) to draw the line." Okay, so, sounds like it doesn't need recasting, just redrawn? That makes a large investment of power more worthwhile. But if a demon actually breaks out of the pentagram it needs casting over again.
You can cast a ten square foot pentagram in ten seconds for ten fatigue. Nice. But not fast enough once battle is joined, and not resilient enough to feet.
But it's a fiddly pain, it not being clear, or giving any numbers.
Also, given you can use enchantment rules to make it, the inventive player is going to have all sorts of thoughts about portable versions, and the description just doesn't go there.
Spell Shield is a prereq for pentagram and protects against fewer things differently but does have a magic item listed. A spell shielding rug or area of floor costs 400 per yard of radius. Which is very different maths indeed from the cost per square foot of pentagram. Which you'd think could also be cast on a rug, and can certainly go on an area of floor.
I know magic is under no obligation to be logical, but rules certainly are, if they're going to be playable by fiddly clever people.
Really, they couldn't have given a single example with radius? *sigh*
ANYway, I got sidetracked with math and that was my afternoon.
Is a good thing I find this fun.
no subject
Date: 2018-01-12 05:17 pm (UTC)I agree that it is stupid not to indicate (1) what part of the pentagram is used to calculate the area and (2) if that's the circle, basing the cost on radius. Hell, if that's not the circle, the cost should still be based on radius or some comparable measurement (center to point of star; center to point of pentagon, whatever) because "10 sq feet" is a ridiculous number for anything other than a square, and, as per the title of the spell, it's not going to be square when it's done.