I'm a little bit confused as to how poison is intended to work and I'm hoping you guys can clarify for me.

1. According to page 128 of the KAP core, poison has a Potency rating. I'm not sure what the Potency rating is or what its proper range should be. How do I determine it?

2. On that same page, it says that the victim of the Poison must make a CON roll in opposed resolution with the poison's Potency roll (1d20 + Potency). It then says to check the CON roll against a chart also listed on that page. First, how do I determine the result of the Potency roll? What am I rolling against? And second, based on the chart, the Potency roll doesn't seem to matter. Generally, with opposed resolution there seems to be a matrix of results, like the Harvest Results table in the Book of the Manor. But in this case, only the CON roll seems to matter. Am I missing something?

I'm a little bit confused as to how poison is intended to work and I'm hoping you guys can clarify for me.

1. According to page 128 of the KAP core, poison has a Potency rating. I'm not sure what the Potency rating is or what its proper range should be. How do I determine it?

2. On that same page, it says that the victim of the Poison must make a CON roll in opposed resolution with the poison's Potency roll (1d20 + Potency). It then says to check the CON roll against a chart also listed on that page. First, how do I determine the result of the Potency roll? What am I rolling against? And second, based on the chart, the Potency roll doesn't seem to matter. Generally, with opposed resolution there seems to be a matrix of results, like the Harvest Results table in the Book of the Manor. But in this case, only the CON roll seems to matter. Am I missing something?


You haven't missed something, Thor, you have noticed something: the rule is a mess and makes no sense at all.

The POT roll should if it follows the rest of the rules be 1d20 equal to or lower than POT; 1d20+POT makes little sense. No other roll is made like that in the rules. And "win", "tie" and "loss" should be the only three results, possibly with a "partial success" too, as per the rules for opposed resolution. A critical might be a tie, so it should read "win and critical". A fumble might also be a tie (both fumble = a tie).

There are some tables in the book of battle that has the same problems, and confuses two things. A single roll can be a crit, success, failure or fumble. An opposed resolution can be a win, loss or tie, with a possible "partial success". This are two different things, as far as I can understand.

How I would resolve poison, just as a quick-and-dirty system (would also work fairly well for the effects of disease):

POT result
CON result CRITICAL SUCCESS FAILURE FUMBLE
CRITICAL unhealthy unhealthy no effect immunity
SUCCESS POT x 1 unhealthy unhealthy no effect
FAILURE POT x 2 POT x 1 unhealthy unhealthy
FUMBLE deceased POT x 2 POT x 1 unhealthy


On any red outcome, the character also takes POT-CON damage if the CON roll was less than or equal to that of the POT roll.

I've always treated poison as any other damage, with CON as armor. So for a poison with potency 8d6 damage, I would roll damage (say 30) and then substract the knight's CON (say 14) calculate to total poison damage (here: 16). This simple resolution gives the following possible results:
-- no damage
-- little damage = small poisoning
-- greater than CON damage = major poisoning (major wound)
-- damage greater than HP = mortal poisoning
This method also allows the game master to more or less predict the lethalness of a poison.

Great stuff, Sir Trout!

I'd second Sir Trout's solution. Nothing wrong with having POT do multi-dice damage I just like using opposed rolls wherever possible, meshes nicely with the rest of the rules. Gotta love that stone cold "deceased" result as well.

Thanks for all the responses guys!

I'm leaning toward Trout's solution, if only because it's closer to the procedure in the book (and I'm a sucker for matrices).

If I do go that route though, what's the best way to set the Potency of the poison? What's an appropriate range? 1-20?

Note, this isn't a hypothetical. At the end of our last session, one of the PKs (whose brother had died at the hands of Sir Blaines of Levcomagus the previous year) disguised himself, worked his way into court and slipped hemlock into Sir Blaines' wine. Not very honorable, to be sure, but young Sir Guy is cruel and reckless.

We got to the point where we needed to resolve the results of the poisoning and had no idea what to do. Right now, Sir Blaines is sort of a Schroedinger's Knight.

Poison Dose POT Onset Duration Symptoms
Aconite 2-3 caps 6 Few minutes Varies Vomiting, diarrhea, seizure
Adder, Asp 1 bite 8 Few minutes Hours Pains, anguish, collapsus, necrosis, edema.
Antimony 1 oz 2 Few minutes Varies Vomiting, diarrhea, respiratory distress
Arsenic 1 oz 16 Few minutes Varies Vomiting, diarrhea, respiratory distress
Bees/Wasps 5 stings 1 Few minutes 2 days Pain, shock, collapse, lung edema
Belladonna 1 fruit 1 Few minutes Varies Excitation, spasms, phobia of light, thirst.
Bittersweet 1 fruit 1 Instant Varies Sickness, diarrhea, agoraphobia, cold.
Cobra 1 bite 16 Few minutes Hours Pain, anguish, collapse, necrosis, edema
Death Cap 1 cap 10 8–16 hours 2–5 days Sickness, colic, collapsus.
Hemlock 2–3 grams 10 Few minutes Varies Vision loss, sickness, diarrhea, paralysis
Henbane 1 leaf 1 Few minutes Varies Nausea, vomiting, amnesia
Lead 1 oz 4 Few minutes Varies Muscle pain, headaches, anemia, brain damage
Mandrake 1 fruit 1 30–60 minutes 24–48 hours Nausea, vomiting, hallucinations
Opium 1 fruit 6 Few minutes Varies Euphoria, agitation, nervousness
Scorpion 1 sting 8 Few minutes 10 hours Pain, anguish, lung edema.
Silphium 1 oz 8 1 day Varies Nausea, vomiting, death
Spurge contact 6 Instant 2–3 days Anguish, fever, paralysis; blindness if sprayed in the eyes.
Wolfsbane contact 10 10–20 minutes Varies Cold sweat, pains, vomiting, colic, failure.
Yew 3-4 leaves 8 Few minutes Varies Collapse, convulsions, diarrhea, vomiting, coma

~ Potency is proportional to the dose (e.g., ten fresh henbane leaves have POT 10).
~ Prepared poisons — as opposed to fresh ones — generally work at half the listed POT.
~ The skill for preparing poisons is, frighteningly enough, Chirurgery. Beware of clergymen and women bearing gifts.
~ The number of bee/wasp stings per round per victim depends on the size of the nest or hive. Assume 25 wasp stings per round for very large nests, and 50 bee stings for very large hives.

[Poison details courtesy of Cthulhu Dark Ages and Cthulhu Invictus. That is not dead which can eternally serve as source material for other games.]

Further poison details, courtesy of Rome: The Life And Death Of The Republic...

• Henbane -- Symptoms: Rapid onset within minutes of ingestion, dry mouth, abnormally rapid heartbeat and a progression of neurological symptoms varying from sedation to delirium, hallucination, mania, paralysis, coma and death.

• Thorn Apple -- Symptoms: Similar to henbane. Seeds produce mainly maniacal symptoms, whilst leaves tend towards stupor and coma. Survivors have amnesia of the event.

• Deadly Nightshade -- Symptoms: As for henbane. Known as strychnos, spears were sometimes coated with it.

• Mandrake -- Symptoms: Dry mouth and rapid heartbeat, but neurologically it causes sedation, motor depression and death via heart failure.

• Aconite -- Symptoms: Rapid onset of numbness and tingling of the mouth and throat which spreads over the rest of the body; pain and twitching of the muscles, progressing to general weakness, cold and clammy extremities, irregular heart rhythm and abnormally low blood pressure, respiratory paralysis, drowsiness, convulsions, stupor and death. Extremely poisonous
even in small doses.

• Hemlock -- Symptoms: Rapid onset of nausea, salivation and vomiting, abdominal pain, headache and degrees of mental confusion. General weakness may be associated with convulsions, and death is caused by progressive paralysis and respiratory failure.

• White hellebore -- Symptoms: Rapid onset of tingling over the whole body, sneezing, vomiting and diarrhea, followed by abnormally low blood pressure, cardiovascular collapse and respiratory paralysis causing death.

• Colchicum (autumn crocus) -- Symptoms: Tingling of the whole mouth and throat, after 2-6 hours it is followed by an impaired ability to swallow, nausea, vomiting and diarrhea (often bloody). Circulation collapse may follow, with general paralysis, often convulsions, and death due to respiratory failure.

• Yew -- Symptoms: After approximately one hour there is onset of dizziness, vomiting, rapid heartbeat, dilation of the pupils, dilation of the blood vessels causing a reddish face, and shallow breathing. Death results from respiratory paralysis. Scythians were said to dip their arrows in yew-sap. (Pretty sure the Cymry, Irish and/or Picts would use similar tactics.)

• Opium -- Symptoms: Induces a somniferous state with euphoria and pinpoint pupils, progressing to stupor with muscular relaxation, slow respiration and ultimately death from respiratory failure. Pliny wrote that opium was sometimes used by elderly Romans to commit suicide.

• Fly Agaric Mushrooms -- Symptoms: Within minutes to 2 hours, salivation, excessive production of tears, breathing problems and severe abdominal pain with diarrhoea. Vertigo and progressive mental symptoms like confusion, delirium, excitement (occasionally convulsions) may lead to coma and death within hours.

• Panther Cap Mushrooms -- Symptoms: Like the Fly Agaric above, but with slower onset and higher fatality.

• Death Cap Mushrooms -- Symptoms: Latent period of 6-15 hours is followed by abdominal pain, vomiting and diarrhea (often bloody). Renal failure then sets in with death 2-3 days later, usually in hepatic coma.

[hr]
And some quick-and-dirty rules for making poisons, antidotes and medicines: To concoct a poison or medicine, a character must possess the Chirurgery skill. The brewer is limited by their skill level -- no one can produce either of a POT greater than their Chirurgery score unless they roll a critical success. A practitioner of Chirurgery can brew a great range of different types, if they can locate the correct ingredients. Each dose takes at least several hours to produce. Medicines reduce the POT of a disease or substitute for a character's CON. Antidotes do the same, except for poison instead.

Poison Dose POT Onset Duration Symptoms
Aconite 2-3 caps 6 Few minutes Varies Vomiting, diarrhea, seizure
Adder, Asp 1 bite 8 Few minutes Hours Pains, anguish, collapsus, necrosis, edema.
Antimony 1 oz 2 Few minutes Varies Vomiting, diarrhea, respiratory distress
Arsenic 1 oz 16 Few minutes Varies Vomiting, diarrhea, respiratory distress
Bees/Wasps 5 stings 1 Few minutes 2 days Pain, shock, collapse, lung edema
Belladonna 1 fruit 1 Few minutes Varies Excitation, spasms, phobia of light, thirst.
Bittersweet 1 fruit 1 Instant Varies Sickness, diarrhea, agoraphobia, cold.
Cobra 1 bite 16 Few minutes Hours Pain, anguish, collapse, necrosis, edema
Death Cap 1 cap 10 8–16 hours 2–5 days Sickness, colic, collapsus.
Hemlock 2–3 grams 10 Few minutes Varies Vision loss, sickness, diarrhea, paralysis
Henbane 1 leaf 1 Few minutes Varies Nausea, vomiting, amnesia
Lead 1 oz 4 Few minutes Varies Muscle pain, headaches, anemia, brain damage
Mandrake 1 fruit 1 30–60 minutes 24–48 hours Nausea, vomiting, hallucinations
Opium 1 fruit 6 Few minutes Varies Euphoria, agitation, nervousness
Scorpion 1 sting 8 Few minutes 10 hours Pain, anguish, lung edema.
Silphium 1 oz 8 1 day Varies Nausea, vomiting, death
Spurge contact 6 Instant 2–3 days Anguish, fever, paralysis; blindness if sprayed in the eyes.
Wolfsbane contact 10 10–20 minutes Varies Cold sweat, pains, vomiting, colic, failure.
Yew 3-4 leaves 8 Few minutes Varies Collapse, convulsions, diarrhea, vomiting, coma

~ Potency is proportional to the dose (e.g., ten fresh henbane leaves have POT 10).
~ Prepared poisons — as opposed to fresh ones — generally work at half the listed POT.
~ The skill for preparing poisons is, frighteningly enough, Chirurgery. Beware of clergymen and women bearing gifts.
~ The number of bee/wasp stings per round per victim depends on the size of the nest or hive. Assume 25 wasp stings per round for very large nests, and 50 bee stings for very large hives.

[Poison details courtesy of Cthulhu Dark Ages and Cthulhu Invictus. That is not dead which can eternally serve as source material for other games.]


Nice stuff. These values strike me as a little low for KAP tho. If I recall correctly, CoC figures HP by taking the average of CON & SIZ whereas KAP totals them. To maintain the same level of lethality you'd need to bump these numbers up a notch. +50% across the board?

Nice stuff. These values strike me as a little low for KAP tho. If I recall correctly, CoC figures HP by taking the average of CON & SIZ whereas KAP totals them. To maintain the same level of lethality you'd need to bump these numbers up a notch. +50% across the board?


The numeric scale used for CON is the same, however, and that is what POT is opposed against. Greg's rules for poison damage appear to take the difference in total hit points into account. Pendragon is in many ways a hack of Basic Role Playing, just as Houses Of The Blooded is in many ways a hack of FATE. Given that Greg had a hand in both KAP and BRP, I'm fairly certain he knows what he's doing.

Interesting that Cthulhu Dark Ages considers opium a poison, when in later periods it was considered a mere drug. Did it have the perception of being a poison in ancient Rome and in medieval Europe?

Would alcohol poisoning come into play here, too?

Most drugs and medicines are poisons, taken in too large a dose, which is why formulating them requires testing. And yes, you could use the above rules to adjudicate alcohol poisoning.

Cool. Thanks, Trout! I might use these to try and work up something regarding allergic reactions, too. Say a foe knows that one of the player knights is allergic to mead, for instance...

Just the other day I had the chance to take a look at the 5.1 rulebook and decided to look for changes and differences. I noticed, among other things I did not know about, that the new edition had a box inserted with the double d20 rule from the GPC. And suddenly the poison rules made sense …

Allow me to quote the OP:



I'm a little bit confused as to how poison is intended to work and I'm hoping you guys can clarify for me.

1. According to page 128 of the KAP core, poison has a Potency rating. I'm not sure what the Potency rating is or what its proper range should be. How do I determine it?

2. On that same page, it says that the victim of the Poison must make a CON roll in opposed resolution with the poison's Potency roll (1d20 + Potency). It then says to check the CON roll against a chart also listed on that page. First, how do I determine the result of the Potency roll? What am I rolling against? And second, based on the chart, the Potency roll doesn't seem to matter. Generally, with opposed resolution there seems to be a matrix of results, like the Harvest Results table in the Book of the Manor. But in this case, only the CON roll seems to matter. Am I missing something?


You can simply assign a Potency rating to the poison and then roll 1d20 for the poison to “act”, determining success or failure (the poison cannot critical succeed or fail). This is opposed as usual by the CON roll of the person poisoned.

How do you know how high the Potency rating should be? If the poison succeeds and the victim fails his roll, he takes damage equal to Potency. An average NPC knight has about 28 to 30 HP; Potency 30 will thus be a good candidate for a truly deadly poison. If the victim manages a partial success (a likely outcome for PKs with their high CON ratings), he still takes 15 points damage and is unhealthy, but he will recover. Probably.

If you want to keep Potency between 1 and 20, i.e. on the same level as skills, you could rule that the poison “attacks” repeatedly, say once per day, until a successful Chirurgery roll is made to counter the poison (may require a specific antidote or special knowledge). This gives the victim a decent chance for total or partial success in the opposed resolution; he will be unhealthy, but suffer little to no damage. Even if he fails, a Potency 10 poison still leaves him several days during which a leech can attempt to counter the poison. Everything with Potency 15 or higher is potentially deadly in one day (if the victim fumbles his roll).

[Edit: The latter option gives poisoned victims a chance to dramatically waste away while everbody rushes around trying to find the antidote or the miracle cure. I suggest having the poison make its daily “strike” at midnight, in opposition to natural healing, which occurs on sunday noon.]