Aussiegamer
First Post
I think the craft DC is too high as well, maybe a 17 or such would be about right. You are just concentrating it to make it more powerful for weaponisation, so maybe a +2 for a higher damage???
d20 Modern: Chlorine Gas
- Thread starter HeapThaumaturgist
- Start date
DarkKestral
First Post
Actually, I'd say this would be a DC 15-17 as well. It's REALLY easy to make in lethal quantities... You just need some rock salt, (NaCl, aka common 'table' salt) water and electricity to synthesize it, plus your container. As for weaponization, realize that the stuff, as typically produced, is already a poison that is suitable for weaponization. All that weaponization of chlorine means is that you've built a system to disperse it in atmosphere. That's not hard to do. Fans work, as do bombs of a certain type. The concentrated stuff would be DC 15-17 to make with such a system.
However, I think you're all underestimating the damage. This was one of the most widespread means of chemical attack in WWI, along with mustard gas, which is a chlorine-containing compound. They are both rather lethal, though somewhat obvious when used.
I would use something like this:
Fort save: DC 20
Damage: 1d6 Con, 3d8 Con
(it's not immediately lethal, but after a minute minute or so, chances are you'll be dead or nearly so.)
As a result, this should have a high PDC, to render it inline with most other poisons, but... it's actually really cheap to make. The main problem with giving it a low PDC is that it's not readily available in mass quantities, and storage is somewhat difficult, due to it's reactivity. It should probably be PDC 12-16 (it'll take some searching, but it's cheap...) or so.
However, for various reasons, I'd give it a Lic (+1) restriction at the least, possibly even increasing to Res (+2), as owning it in mass quantities will incur some regulatory hassles and oversight (OSHA-type groups, the FBI, the EPA, and various police agencies) and thus, you probably don't wanna buy it too often. Most people who need it in large quantities are prone to recycling it if possible, synthesizing their own, or buy it in extreme bulk. Therefore, quantities in the level most PCs would have access to would in fact be signs of it being used for terrorist-type activities. (However, there are more effective poisons, some of which are just as easily made.)
EDIT: to point out just how dangerous this stuff is, my chemistry professors (my being a chemistry student in a university, I've had a few of them) have lists of various chemical experiments. One of them involves reacting pennies with hydrochloric acid to produce copper (II) chloride. It's not a safe one to do, because even with a small (2-3, IIRC) number of pennies per person, the chlorine produced is enough to kill ~30 people easily, and very easy to produce. Once you're moving into the multi-kilogram range, you're talking warhead-worthy.
Plus, it has a nasty side ability apart from burning your lungs.. it asphyxiates you, being heavier than air. Asphyxiation is nasty.
However, I think you're all underestimating the damage. This was one of the most widespread means of chemical attack in WWI, along with mustard gas, which is a chlorine-containing compound. They are both rather lethal, though somewhat obvious when used.
I would use something like this:
Fort save: DC 20
Damage: 1d6 Con, 3d8 Con
(it's not immediately lethal, but after a minute minute or so, chances are you'll be dead or nearly so.)
As a result, this should have a high PDC, to render it inline with most other poisons, but... it's actually really cheap to make. The main problem with giving it a low PDC is that it's not readily available in mass quantities, and storage is somewhat difficult, due to it's reactivity. It should probably be PDC 12-16 (it'll take some searching, but it's cheap...) or so.
However, for various reasons, I'd give it a Lic (+1) restriction at the least, possibly even increasing to Res (+2), as owning it in mass quantities will incur some regulatory hassles and oversight (OSHA-type groups, the FBI, the EPA, and various police agencies) and thus, you probably don't wanna buy it too often. Most people who need it in large quantities are prone to recycling it if possible, synthesizing their own, or buy it in extreme bulk. Therefore, quantities in the level most PCs would have access to would in fact be signs of it being used for terrorist-type activities. (However, there are more effective poisons, some of which are just as easily made.)
EDIT: to point out just how dangerous this stuff is, my chemistry professors (my being a chemistry student in a university, I've had a few of them) have lists of various chemical experiments. One of them involves reacting pennies with hydrochloric acid to produce copper (II) chloride. It's not a safe one to do, because even with a small (2-3, IIRC) number of pennies per person, the chlorine produced is enough to kill ~30 people easily, and very easy to produce. Once you're moving into the multi-kilogram range, you're talking warhead-worthy.
Plus, it has a nasty side ability apart from burning your lungs.. it asphyxiates you, being heavier than air. Asphyxiation is nasty.
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Aussiegamer
First Post
Its not that powerful compared to mustard gas or sarine or such, so damage and DC should be quite low. It also takes a long time to kill about 30 minutes. I beleive that sarine is hand full of minutes
And if its that easy to make then 12-14 should be the craft DC
The secondary affect is not the continued exposure but the second save. You don't have to be in the room as the gas for the 2nd save.
And if its that easy to make then 12-14 should be the craft DC
The secondary affect is not the continued exposure but the second save. You don't have to be in the room as the gas for the 2nd save.
DarkKestral
First Post
It's not as lethal as sarin, yes, but considering the exposure level after 1 minute can still be lethal... (and few people remember that with chlorine, you're fighting off nausea, asphyxiation, and your body is undergoing toxin damage, plus you can't see well/at all. It's still a nasty cocktail of effects, even if you do lower damage, since your PCs will be nauseated, poisoned, trying to avoid breathing, AND be unable to see, and probably taking damage every round from chemical burns) 1d6 Con secondary damage won't exactly 'mimic' it. If you're doing multiple doses per round, it may.
Still, adjust it down if need be. My point was that on average, most people, when exposed to even seemingly minute quantities WILL die after even a short exposure. If you're releasing enough gas to create a 'weaponized' version, it won't generally take long to kill.
The reason I think 'weaponized' chlorine should be DC 15 or so to make is the combination of storage + a 'safe' release mechanism. Someone with a basic knowledge of chemistry can make chlorine, but it takes a slightly more advanced level of skill to figure out a way to attach a mechanism that will allow controlled release rather than be rendered useless by chlorine's general reactivity. It's not that hard, but it does require some degree of specialized skill and intelligence. However, as a poison, I probably would be hesitant to allow PCs to use it, because of the combination of relatively high lethality, and cheap production. The more advanced chemical weapons at least are nice in that they're so deadly that if your PCs screw up, chances are good they took themselves out. Chlorine's slow enough that they'd have a chance to save themselves...
EDIT: While this would be a good chance for PCs to use some 'underdeveloped' skills like Craft (chemical) or Knowledge (tactics) to recognize the agent, or Craft (structural) to recognize the vacuum seal equipment on the doors and in the rooms, and the like...
I don't like the concept of using lethal agents like this in my games though, generally the weapon agents have so many negative effects it could easily make the players think that they are not being given a fair chance.
Additionally, I don't like that sort of save-or-die trap unless PCs have a chance to know about it ahead of time enough to buy equipment and prepare some kind of defense. It's OK in some games but I just don't like using TPK inducer poisons without some chance for PCs to make a few choices. (AKA a break out where the party can go the long way around, which is safer, but they risk getting caught; or the party can go the short way, which is significantly less likely to get them caught, but they run a real risk of TPKing themselves) Anyone not somewhat familiar with chemistry is not likely to be aware what a description of a chemical trap might be unless the GM knows as much or more about the agent in question.
Still, adjust it down if need be. My point was that on average, most people, when exposed to even seemingly minute quantities WILL die after even a short exposure. If you're releasing enough gas to create a 'weaponized' version, it won't generally take long to kill.
The reason I think 'weaponized' chlorine should be DC 15 or so to make is the combination of storage + a 'safe' release mechanism. Someone with a basic knowledge of chemistry can make chlorine, but it takes a slightly more advanced level of skill to figure out a way to attach a mechanism that will allow controlled release rather than be rendered useless by chlorine's general reactivity. It's not that hard, but it does require some degree of specialized skill and intelligence. However, as a poison, I probably would be hesitant to allow PCs to use it, because of the combination of relatively high lethality, and cheap production. The more advanced chemical weapons at least are nice in that they're so deadly that if your PCs screw up, chances are good they took themselves out. Chlorine's slow enough that they'd have a chance to save themselves...
EDIT: While this would be a good chance for PCs to use some 'underdeveloped' skills like Craft (chemical) or Knowledge (tactics) to recognize the agent, or Craft (structural) to recognize the vacuum seal equipment on the doors and in the rooms, and the like...
I don't like the concept of using lethal agents like this in my games though, generally the weapon agents have so many negative effects it could easily make the players think that they are not being given a fair chance.
Additionally, I don't like that sort of save-or-die trap unless PCs have a chance to know about it ahead of time enough to buy equipment and prepare some kind of defense. It's OK in some games but I just don't like using TPK inducer poisons without some chance for PCs to make a few choices. (AKA a break out where the party can go the long way around, which is safer, but they risk getting caught; or the party can go the short way, which is significantly less likely to get them caught, but they run a real risk of TPKing themselves) Anyone not somewhat familiar with chemistry is not likely to be aware what a description of a chemical trap might be unless the GM knows as much or more about the agent in question.
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HeapThaumaturgist
First Post
DarkKestrel, thanks for the reply. 
If its that easy, I'll probably crank the DC and such down a bit. Blue Vitriol (aka Copper(II) Sulfate) has a PDC of 3 and a Craft DC of 9 ... you can find it in kids' chemistry sets, as far as I know ... makes pretty crystals ... not sure how you'd go about using it as an injury poison.
How large of an area of effect would releasing just a few ounces of compressed chlorine gas, 90-100 grams, become? I'm not sure about the expansion of gasses and the such.
EDIT: I'm hesitant to allow it as well, which is why I'm trying to find out as much information as I can. In general, I have on hand a method by which a character could produce about 100g of pure chlorine gas for around PDC 15 and a series of DC 15 skill checks. There would be no real problem with transportation or releasing the gas because ... well ... it'd be magic.
--fje
If its that easy, I'll probably crank the DC and such down a bit. Blue Vitriol (aka Copper(II) Sulfate) has a PDC of 3 and a Craft DC of 9 ... you can find it in kids' chemistry sets, as far as I know ... makes pretty crystals ... not sure how you'd go about using it as an injury poison.
How large of an area of effect would releasing just a few ounces of compressed chlorine gas, 90-100 grams, become? I'm not sure about the expansion of gasses and the such.
EDIT: I'm hesitant to allow it as well, which is why I'm trying to find out as much information as I can. In general, I have on hand a method by which a character could produce about 100g of pure chlorine gas for around PDC 15 and a series of DC 15 skill checks. There would be no real problem with transportation or releasing the gas because ... well ... it'd be magic.
--fje
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DarkKestral
First Post
Err.. 100 grams of pure Cl2 is roughly enough to kill 30 people in a ~10x10x10 room, assuming no leakage, in about 30 minutes, IIRC. They will note a smell, however, and begin coughing WELL below that amount.
Also, depending on how long the exposure is, it can be lethal in very small concentrations, around as 30 ppm though it will take 30-40 minutes 'per dose'. Around 1000 ppm (one gram per kilogram) it will kill in a number of breaths. Thus, if you REALLY need to know how deadly it is.. you'll have to do some math, since you'll need to figure out deviations from a chemist's STP and the size of the room. However, without doing the math, I'd say that, with a dose like yours, you'll need 30 minutes or so to kill with it. After 15 minutes, your PCs will probably be really getting some major Con damage. Perhaps a bit less, but not by much. However, nausea, burning, and minor asphyxiation will have set in in a matter of minutes. Blinding would simply be a matter of whether or not your PCs close their eyes. At that concentration, it's probably not going to be visible, though their eyes would itch something fierce.
The main problem with d20's poison rules is they are not great for long term dosage. They are excellent for one-shot poisons, like most assassin poisons, but for time-dependent poisons, they are very poor. A 'one-shot' version of chlorine will kill almost immediately, but a realistic slow version may just have the PCs use something like Vigor or one of the con-booster spells and then the PCs may just ignore it.
EDIT: Heap... the PDC would be for purchase. DC 15 to produce would be to get it from water and salt, which means it's ALMOST PDC 0 to produce, but perhaps PDC 3-4 to buy the necessary glassware. However, production would produce NaOH in the bargain, providing a concentrated base with which to make 'acid' flasks...It wouldn't be possible to take 10 on the checks, since the penalty for failure could be self-exposure to the poison. A Smart Hero-type Talent or AdC/PrC ability might allow a 10 on the check, however.
Also, depending on how long the exposure is, it can be lethal in very small concentrations, around as 30 ppm though it will take 30-40 minutes 'per dose'. Around 1000 ppm (one gram per kilogram) it will kill in a number of breaths. Thus, if you REALLY need to know how deadly it is.. you'll have to do some math, since you'll need to figure out deviations from a chemist's STP and the size of the room. However, without doing the math, I'd say that, with a dose like yours, you'll need 30 minutes or so to kill with it. After 15 minutes, your PCs will probably be really getting some major Con damage. Perhaps a bit less, but not by much. However, nausea, burning, and minor asphyxiation will have set in in a matter of minutes. Blinding would simply be a matter of whether or not your PCs close their eyes. At that concentration, it's probably not going to be visible, though their eyes would itch something fierce.
The main problem with d20's poison rules is they are not great for long term dosage. They are excellent for one-shot poisons, like most assassin poisons, but for time-dependent poisons, they are very poor. A 'one-shot' version of chlorine will kill almost immediately, but a realistic slow version may just have the PCs use something like Vigor or one of the con-booster spells and then the PCs may just ignore it.
EDIT: Heap... the PDC would be for purchase. DC 15 to produce would be to get it from water and salt, which means it's ALMOST PDC 0 to produce, but perhaps PDC 3-4 to buy the necessary glassware. However, production would produce NaOH in the bargain, providing a concentrated base with which to make 'acid' flasks...It wouldn't be possible to take 10 on the checks, since the penalty for failure could be self-exposure to the poison. A Smart Hero-type Talent or AdC/PrC ability might allow a 10 on the check, however.
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Plane Sailing
Astral Admin - Mwahahaha!
DarkKestral said:
I would guess that if you were trapped in an enclosed area with it, you would be re-exposed to the poison every round and would have to save again every round (like if a snake bites you again you have to save again).
Thus you could have a moderately low damage, and I'd go with something like
primary: nausea
secondary: 1d4 Con
So if you get affected by the primary effect, the nausea will probably prevent you escaping from the room, and after a minute the secondary effects start kicking in - and if you've been in there a minute you might have to make 10 secondary saves against 1d4 Con for the next minute or so.
This would mean that if you were in a chlorine cloud for just a round or two it would be nasty and potentially life threatening for those of weaker constitution, but if you were trapped in a room or other enclosed space with chlorine gas it could be very nasty indeed...
DarkKestral
First Post
Oh certainly. But the problem with chlorine is that it's effects are almost always either immediate, or take many minutes before you'll notice. This is also a similar effect to most modern poisons. Therefore, a low dose version could be
Initial damage: nausea
secondary damage: 1 con
(BTW, this is what I'd use to model the 'damage' effects at the dose you mentioned Heap.)
but 10 'doses' taken in one round could easily be:
initial damage: 1d8 con, asphyxiation
seconday damage: 4d8 con
It's not like it's multiple doses, cause it really isn't.. it's just a much more massive comparative systemic effect. modeling that becomes a pain.
Initial damage: nausea
secondary damage: 1 con
(BTW, this is what I'd use to model the 'damage' effects at the dose you mentioned Heap.)
but 10 'doses' taken in one round could easily be:
initial damage: 1d8 con, asphyxiation
seconday damage: 4d8 con
It's not like it's multiple doses, cause it really isn't.. it's just a much more massive comparative systemic effect. modeling that becomes a pain.
Mustrum_Ridcully
Legend
The D20 rules for poisons are relatively simply, and poisons are by for not as deadly as many real poisons are. So, if you want a balanced version of Chlorine Gas, you shouldn't make it to effective, even if it is in reality.
If you want a realistic one, you could give it dramatic effects, but keep in mind that all other statted poisons are not balanced by "realismn".
If you want a realistic one, you could give it dramatic effects, but keep in mind that all other statted poisons are not balanced by "realismn".
(Psi)SeveredHead
Adventurer
Does anyone recall the sarin gas attack by that cult in Tokyo? The gas was released in a crowded subway station and still no one died.
I don't think poison is necessarily that deadly (at least sarin doesn't seem to be). On a similar note, biological warfare has virtually never worked.
I don't think it's necessary to boost the Con damage (you could keep it at one or 1d4, for instance) but increase the DC with Concentration. Obviously the longer you're exposed, the more Con damage you take.
I don't think poison is necessarily that deadly (at least sarin doesn't seem to be). On a similar note, biological warfare has virtually never worked.
I don't think it's necessary to boost the Con damage (you could keep it at one or 1d4, for instance) but increase the DC with Concentration. Obviously the longer you're exposed, the more Con damage you take.
