(PF) How much space can you meaningfully block with 10 cubic feet of burning wood?

[Coidzor]

Assuming you can shape said wood however you want using Wood Shape and you can have several of them due to the duration of Shrink Item being measured in days per caster level.

That is to say, the Wooden component of it has to be 10 cubic feet, but it can be expanded to occupy a greater volume than that due to empty space.

Also, for about how long would it burn at its most expansive? I'm looking for something that would discourage or prevent a human passing through it without first stopping to put out the fire.

What about blocking off 3' to 5' wide stone steps?

Edit: Pathfinder, sorry, forgot to mention that.

[Kelb_Panthera]

10 cubic feet isn't much at all. You could fill a 5 ft square to about 4-5~ish inches. Depending on the kind wood (pine burns hotter and faster than oak, for example), you could see it burn with open flames for maybe 45 minutes to an hour. You could cover 4 five foot squares to about an inch but it'll only burn for a few minutes before it's just coals.

[Jack_Simth]

Assuming you can shape said wood however you want using Wood Shape and you can have several of them due to the duration of Shrink Item being measured in days per caster level.

That is to say, the Wooden component of it has to be 10 cubic feet, but it can be expanded to occupy a greater volume than that due to empty space.

Also, for about how long would it burn at its most expansive? I'm looking for something that would discourage or prevent a human passing through it without first stopping to put out the fire.

What about blocking off 3' to 5' wide stone steps?

Ten cubic feet isn't much... but yes, you could make something of a portable wall by way of a lattice work. You want to stop something mostly human; OK. Most humans aren't going to get through an area that's 10" by 10" without a lot of work (it's a 'tight space', DC 30 escape artist check for a human, I think). If you make a lattice with gaps of that size out of bars that are 2"x2" square beams, then your wall is two inches thick, and the actual wood takes up 88 of every 288 cubic inches on average, and that unit fills one square foot. Ten cubic feet of wood contains 17,280 cubic inches, so that'd be 196.3636... square feet of wall, which would work out to just about two 10'x10' squares. Wood has hardness-5, and 10 hp/inch of thickness. Assuming damage from fire applies in full, but that hardness applies, then the 1d6 per round of mundane fire would (on average) take a point off of that 20 HP once every six rounds, and the burning wall would last 120 rounds (12 minutes) on average if nobody was doing anything else to it. I find that these assumptions produce results that are "close enough" to how long wood lasted in campfires growing up for my tastes, but your DM may decide on different rules.

If you go with 3"x3" square beam bars and 9"x9" empty spaces, then that's 189 cubic inches of wood per one square foot, and you get 91 square feet of barrier, which is just under a 10'x10' lattice wall. This wall has 30 hp, but the same hardness, and is expected to last 180 rounds using the same assumptions as before.

If you go with 4"x4" square beam bars and 8"x8" empty spaces, then that's 320 cubic inches of wood per square foot, so you get 54 square feet, which is about two 5' squares. This wall has 40 hp, still hardness 5, and is expected to last 240 rounds of mundane being on fire.

If you go with 5"x5" square beam bars and 7"x7" empty spaces, then that's 475 cubic inches of wood per square foot of barrier, and you get about 36 square feet, which is one and a half five foot squares. 50 hp, so works out to about 300 rounds on average.

If you go with 6"x6" square beam bars and 6"x6" empty spaces, then that's 648 cubic inches of wood per square foot of barrier, and you get about 26 square feet, so that's about one five-foot square. 60 hp, so works out to about 360 rounds on average.

If you go with a 1"x1" square stick lattice and 11"x11" empty spaces, then that's just 23 cubic inches of wood per square foot, so you get 751 square feet out of it, which works out to a 27 foot square, or 30 5 foot squares. Keep in mind, though, that with that thickness, it'll break if almost anyone hits it at a run. For completeness, though, it'd only have 10 hp, and last just about six minutes on fire.

Keep in mind, though, that the actual damage to the wood by fire is DM call - hardness might not apply. Additionally, those walls are breakable; I'd personally grab the DCs for Simple/Good/Strong doors (13/18/23, respectively... and that DC by all rights should go down as the wall continues to burn) pattern them up starting at the 2" lattice. Additionally, they can take damage from the people behind them (if you're being chased by an equal-level barbarian with a greataxe, the barrier will maybe cost him a standard action to smash to bits before going through the remains and soaking the 1d6 fire damage to kill you anyway if he's built modestly well).


Edit:
As to blocking steps? Assuming that bracing isn't a problem, just use he smaller walls.

Edit 2: Oh yes, and do keep in mind: None of the barriers I listed block Line-of-Effect. This may be useful, or harmful, depending on the exact situation. If you wanted to block line-of-effect for a short period of time, you might put a one inch thick sheet on the back of one of the earlier lattice works. Using a 2" square post lattice with 10" gaps, and a 1" backing to block LoE, you'd use up 232 cubic inches per square foot, and could cover about 74.48 square feet with it - that works out to about three five-foot squares. I imagine it would block line of effect for about 60 rounds (after which the backing will be burned through), and... hmm. What's the total HP? Eh. Probably either 20 or 30, so it'll likely last a total of 120-180 rounds on average.

[Kelb_Panthera]

For clarity's sake, you -did- mean 10 cubic feet and not a 10 foot cube, right? I assumed as much because of shrink item but confirmation would be appreciated.

[Jack_Simth]

Oh, also: You may want to look up the spell "Blockade" from Complete Scoundrel, page 95.

[Coidzor]

For clarity's sake, you -did- mean 10 cubic feet and not a 10 foot cube, right? I assumed as much because of shrink item but confirmation would be appreciated.

Yes, 10 cubic feet. If it was a 10' cube, that'd take care of matters on its own, since I'm pretty sure the battlements and such are 10 feet wide. I would love to be able to make a 10' cube of bonfire wood and shrink it with a 3rd level spell.


Oh, also: You may want to look up the spell "Blockade" from Complete Scoundrel, page 95.

Neat, but 3 rounds or 6 when extended is probably a bit too short. Also I'm doing this in Pathfinder, and for now we're doing PF-only.


Ten cubic feet isn't much... but yes, you could make something of a portable wall by way of a lattice work. You want to stop something mostly human; OK. Most humans aren't going to get through an area that's 10" by 10" without a lot of work (it's a 'tight space', DC 30 escape artist check for a human, I think). If you make a lattice with gaps of that size out of bars that are 2"x2" square beams, then your wall is two inches thick, and the actual wood takes up 88 of every 288 cubic inches on average, and that unit fills one square foot. Ten cubic feet of wood contains 17,280 cubic inches, so that'd be 196.3636... square feet of wall, which would work out to just about two 10'x10' squares. Wood has hardness-5, and 10 hp/inch of thickness. Assuming damage from fire applies in full, but that hardness applies, then the 1d6 per round of mundane fire would (on average) take a point off of that 20 HP once every six rounds, and the burning wall would last 120 rounds (12 minutes) on average if nobody was doing anything else to it. I find that these assumptions produce results that are "close enough" to how long wood lasted in campfires growing up for my tastes, but your DM may decide on different rules.

If you go with 3"x3" square beam bars and 9"x9" empty spaces, then that's 189 cubic inches of wood per one square foot, and you get 91 square feet of barrier, which is just under a 10'x10' lattice wall. This wall has 30 hp, but the same hardness, and is expected to last 180 rounds using the same assumptions as before.

If you go with 4"x4" square beam bars and 8"x8" empty spaces, then that's 320 cubic inches of wood per square foot, so you get 54 square feet, which is about two 5' squares. This wall has 40 hp, still hardness 5, and is expected to last 240 rounds of mundane being on fire.

If you go with 5"x5" square beam bars and 7"x7" empty spaces, then that's 475 cubic inches of wood per square foot of barrier, and you get about 36 square feet, which is one and a half five foot squares. 50 hp, so works out to about 300 rounds on average.

If you go with 6"x6" square beam bars and 6"x6" empty spaces, then that's 648 cubic inches of wood per square foot of barrier, and you get about 26 square feet, so that's about one five-foot square. 60 hp, so works out to about 360 rounds on average.

If you go with a 1"x1" square stick lattice and 11"x11" empty spaces, then that's just 23 cubic inches of wood per square foot, so you get 751 square feet out of it, which works out to a 27 foot square, or 30 5 foot squares. Keep in mind, though, that with that thickness, it'll break if almost anyone hits it at a run. For completeness, though, it'd only have 10 hp, and last just about six minutes on fire.

Keep in mind, though, that the actual damage to the wood by fire is DM call - hardness might not apply. Additionally, those walls are breakable; I'd personally grab the DCs for Simple/Good/Strong doors (13/18/23, respectively... and that DC by all rights should go down as the wall continues to burn) pattern them up starting at the 2" lattice. Additionally, they can take damage from the people behind them (if you're being chased by an equal-level barbarian with a greataxe, the barrier will maybe cost him a standard action to smash to bits before going through the remains and soaking the 1d6 fire damage to kill you anyway if he's built modestly well).


Edit:
As to blocking steps? Assuming that bracing isn't a problem, just use he smaller walls.

Edit 2: Oh yes, and do keep in mind: None of the barriers I listed block Line-of-Effect. This may be useful, or harmful, depending on the exact situation. If you wanted to block line-of-effect for a short period of time, you might put a one inch thick sheet on the back of one of the earlier lattice works. Using a 2" square post lattice with 10" gaps, and a 1" backing to block LoE, you'd use up 232 cubic inches per square foot, and could cover about 74.48 square feet with it - that works out to about three five-foot squares. I imagine it would block line of effect for about 60 rounds (after which the backing will be burned through), and... hmm. What's the total HP? Eh. Probably either 20 or 30, so it'll likely last a total of 120-180 rounds on average.

Nice. Thank you very much. :smallbiggrin:

[Jack_Simth]

Nice. Thank you very much. :smallbiggrin:
Glad to help.

Side note: Having measured both my shoulders and doggie door I once went through, apparently I can make "Tight Space" "The DC noted on the table is for getting through a space where your head fits but your shoulders don’t. If the space is long you may need to make multiple checks. You can’t get through a space that your head does not fit through." DC 30. Even assuming I took 20 on that one... wha? I think the DC may be wrong, as I'm not what I'd call practiced at slipping through small spaces and escaping bonds....

Edit: Oh, nevermind. Turns out the corner-to-corner measurement of that one is one inch wider than my shoulders.

[Coidzor]

Glad to help.

Side note: Having measured both my shoulders and doggie door I once went through, apparently I can make "Tight Space" "The DC noted on the table is for getting through a space where your head fits but your shoulders don’t. If the space is long you may need to make multiple checks. You can’t get through a space that your head does not fit through." DC 30. Even assuming I took 20 on that one... wha? I think the DC may be wrong, as I'm not what I'd call practiced at slipping through small spaces and escaping bonds....

Edit: Oh, nevermind. Turns out the corner-to-corner measurement of that one is one inch wider than my shoulders.

I think most of them will be wearing breastplates or heavier armor, with only maybe a handful wearing chain shirts or lighter. So I think if it's flaming, they'll be less likely to try to squeeze through it.

[Jack_Simth]

I think most of them will be wearing breastplates or heavier armor, with only maybe a handful wearing chain shirts or lighter. So I think if it's flaming, they'll be less likely to try to squeeze through it.
They'll likely chop it to bits, though.

Given the space listing, I'm guessing you're level five. So... assuming for the moment that you're dealing with a mob of 3rd level Str-18 (16 base, +2 racial) Fighters or Warriors with greataxes and power attack and masterwork but not magical weapons...

An axe seems an appropriate weapon for chopping wood, so I figure it'd be full damage. Two handed, so each attack is dealing 1d12+6 before power attack. Power Attack makes that 1d12+9. Hardness-5, so each hit takes off 1d12+4 HP from the lattice (average 10.5). They pretty much only miss on a nat-1, and 95% of 10.5 is just a very small amount over 10 - so that conveniently works out to one attack per inch of thickness on the wood of the lattice per section on average, assuming they don't try for the strength checks. That 3" lattice blocking that ten foot hallway is NOT going to last long when you're running from two guards - they both hit it once on the first round, then the second round one breaches it and the other goes through. This also, of course, assumes that you 'place' the lattice well - hold it out aligned and speak the command word to grow it so that it greets the walls appropriately and jams into place well. Simply throwing it on the ground probably won't get what you want. Do you have a raven familiar? You may need it to speak the command word due to action economy issues (move to pull the small version from your pack, ???? to hold it out correctly, standard for the command word - you'll want an extra action in the mix).

[Coidzor]

Would soaking the wood in oil just make it burn up faster but be hotter?


They'll likely chop it to bits, though.

Given the space listing, I'm guessing you're level five. So... assuming for the moment that you're dealing with a mob of 3rd level Str-18 (16 base, +2 racial) Fighters or Warriors with greataxes and power attack and masterwork but not magical weapons...

An axe seems an appropriate weapon for chopping wood, so I figure it'd be full damage. Two handed, so each attack is dealing 1d12+6 before power attack. Power Attack makes that 1d12+9. Hardness-5, so each hit takes off 1d12+4 HP from the lattice (average 10.5). They pretty much only miss on a nat-1, and 95% of 10.5 is just a very small amount over 10 - so that conveniently works out to one attack per inch of thickness on the wood of the lattice per section on average, assuming they don't try for the strength checks. That 3" lattice blocking that ten foot hallway is NOT going to last long when you're running from two guards - they both hit it once on the first round, then the second round one breaches it and the other goes through. This also, of course, assumes that you 'place' the lattice well - hold it out aligned and speak the command word to grow it so that it greets the walls appropriately and jams into place well. Simply throwing it on the ground probably won't get what you want. Do you have a raven familiar? You may need it to speak the command word due to action economy issues (move to pull the small version from your pack, ???? to hold it out correctly, standard for the command word - you'll want an extra action in the mix).

Several areas would only have a wall on one side and the rest exposed to open air (stairs up a castle wall to the parapet/battlements) or have no wall or only a low wall on a single side (on the battlements/parapet). So it would have to be partially free-standing, whatever shape it takes.

My thoughts for the stairs were to make them shaped like the stairs, it seems like maybe 3 inches thick could cover around 9.5 steps of 4.5' wide, 9" tall steps and be awkward to try to handle, even after chopping it. Or to make a lattice that follows the stairs or even forms a sort of ramp of fire.

As for likely weapons... IIRC, the soldiers there will be using halberds or sword and board with longswords.

No raven familiar, alas. I went with a snek.

[Jack_Simth]

Would soaking the wood in oil just make it burn up faster but be hotter?
Probably, but two things:
1) You're getting into things that are strictly DM call.
2) With the basic assumptions I made earlier, a fire that's 2d6 rather than 1d6 burns the wood up MUCH faster; instead of an average of 60 rounds/inch, you're dealing with an average of 4.4 rounds/inch. A 3d6 fire means the wall lasts just 1.695 rounds/inch on average (and you could lose an entire inch of thickness and then some in a single round).

2d6 deals 2 (1/36 chance), 3 (2/36 chance), 4 (3/36 chance), 5 (4/36 chance), 6 (5/36 chance), 7 (6/36 chance), 8 (5/36 chance), 9 (4/36 chance), 10 (3/36 chance), 11 (2/36 chance), or 12 (1/36 chance) damage each round.

With the same assumptions as before - hardness 5, fire deals full damage to wood but does not ignore hardness - the damage for each roll works out to:
2: 0
3: 0
4: 0
5: 0
6: 1
7: 2
8: 3
9: 4
10: 5
11: 6
12: 7

The weighted average, then, is the damage for each roll, times the probability of each roll, added up. Ignoring the 0's, that's (1*5+2*6+3*5+4*4+5*3+6*2+7*1)/36= 2.27777777... each round. At 10 HP/inch, that's an average of 4.4 rounds per inch of thickness (and short enough that you'll need to end up rolling damage each round).

Applying the same math to a 3d6 fire yields an average of about 5.8981481481... damage/round, which in turn means that the wood lasts an average of 1.695 rounds/inch.

... and that's just from the fire itself, not counting anyone hacking at it.

Several areas would only have a wall on one side and the rest exposed to open air (stairs up a castle wall to the parapet/battlements) or have no wall or only a low wall on a single side (on the battlements/parapet). So it would have to be partially free-standing, whatever shape it takes.Then you're going to get a lot less thickness per segment, and it'll be a lot easier to knock around - ten cubic feet of a dense wood (American White Oak, at 47 pounds per cubic foot, say), is only going to weigh in at 470 pounds. "A character can generally push or drag along the ground as much as five times his maximum load. Favorable conditions can double these numbers, and bad circumstances can reduce them by half or more." - to push or drag 470 pounds, your maximum load must be able to cover 94 pounds... and a medium Strength 10 creature can do that. They only need to get it off the steps. You'll get one round, tops, without the ability to wedge it somewhere.

[Coidzor]

Probably, but two things:
1) You're getting into things that are strictly DM call.
2) With the basic assumptions I made earlier, a fire that's 2d6 rather than 1d6 burns the wood up MUCH faster; instead of an average of 60 rounds/inch, you're dealing with an average of 4.4 rounds/inch. A 3d6 fire means the wall lasts just 1.695 rounds/inch on average (and you could lose an entire inch of thickness and then some in a single round).

2d6 deals 2 (1/36 chance), 3 (2/36 chance), 4 (3/36 chance), 5 (4/36 chance), 6 (5/36 chance), 7 (6/36 chance), 8 (5/36 chance), 9 (4/36 chance), 10 (3/36 chance), 11 (2/36 chance), or 12 (1/36 chance) damage each round.

With the same assumptions as before - hardness 5, fire deals full damage to wood but does not ignore hardness - the damage for each roll works out to:
2: 0
3: 0
4: 0
5: 0
6: 1
7: 2
8: 3
9: 4
10: 5
11: 6
12: 7

The weighted average, then, is the damage for each roll, times the probability of each roll, added up. Ignoring the 0's, that's (1*5+2*6+3*5+4*4+5*3+6*2+7*1)/36= 2.27777777... each round. At 10 HP/inch, that's an average of 4.4 rounds per inch of thickness (and short enough that you'll need to end up rolling damage each round).

Applying the same math to a 3d6 fire yields an average of about 5.8981481481... damage/round, which in turn means that the wood lasts an average of 1.695 rounds/inch.

... and that's just from the fire itself, not counting anyone hacking at it.

Makes sense. I have to wonder whether the hacked up pieces would still provide some impediment though, granted, I suppose shoveling would only take a few standard actions.


Then you're going to get a lot less thickness per segment, and it'll be a lot easier to knock around - ten cubic feet of a dense wood (American White Oak, at 47 pounds per cubic foot, say), is only going to weigh in at 470 pounds. "A character can generally push or drag along the ground as much as five times his maximum load. Favorable conditions can double these numbers, and bad circumstances can reduce them by half or more." - to push or drag 470 pounds, your maximum load must be able to cover 94 pounds... and a medium Strength 10 creature can do that. They only need to get it off the steps. You'll get one round, tops, without the ability to wedge it somewhere.

Any suggestions for something to do to anchor it? So far I'm drawing a blank on that front, aside from using Stone Shape to make a wall to narrow the area and embed parts of the wood lattice in the stone.

[Coidzor]

Seems like smoke sticks might be a cheap way to limit the ability of others to disrupt them.

Thinking about how I can add some poison oak or ivy to them to create some poison smoke.

[Jack_Simth]

Makes sense. I have to wonder whether the hacked up pieces would still provide some impediment though, granted, I suppose shoveling would only take a few standard actions.
I imagine that it would be "difficult terrain" after it was broken into (probably still burning) rubble.

Any suggestions for something to do to anchor it? So far I'm drawing a blank on that front, aside from using Stone Shape to make a wall to narrow the area and embed parts of the wood lattice in the stone.
Well... if you've got stairs and cantelations, and both are built in a highly regular manner, you could probably add spokes or something to tie into those.