D&D 5E Creating a good and simple slow poison

[Stalker0]

Poisons have always been tricky in dnd. On the one hand you want them to work their fantasy motifs, but on the other hand make them too good and they become the go to weapon in every players arsenal.

Current dnd poisons tend to provide some initial effect that either ends quickly or lingers for a while. But if we think of your standard fantasy motif, poisons often work like this:

• Doesn't start in combat. Most of the time the hero doesn't even know they have been poisoned until after the fight, where they find some small cut and then the pain kicks in.
• Always potent. Fantasy poisons like this work even on the toughest heroes. There is no such thing as a "flex it out", tough heroes can endure it for a long time, but eventually without a cure, will die like anyone else or at the very least go into a near death state.
• Slow spiral into death. Untreated poisons are lethal (that's the point!), it starts out small but eventually you will die unless you get cured, treated, or in some cases can get enough rest to barely survive.

The goal here is to create a simple poison system that mimics this kind of behavior.


Slow Poisons
Slow poisons take time to act but are exceptionally lethal. Without treatment, they are almost always fatal.

Onset: This is how long it takes for the poison to start acting. The duration is increased by the creature's constitution bonus (if positive).

Effect: After the onset period, the creature takes 1 Fatigue, +1 fatigue for every constitution penalty they have.

Medicine DC: A successful medicine check done before the onset will stop the poison. After the onset, a success increases the creature's constitution bonus by 2, and a result 10 higher than the DC will give the creature the effects of an Anti-Toxin. A failed medicine check after the onset cannot be retried unless the healer gets access to new remedies or medicines.

Escalation: This is how long until the creature suffers the poison effect again. The duration is increased by the creature's constitution bonus (if positive). After each effect, the escalation time resets. The poison continues to work until the creature is cured or has been dealt 6 fatigue.

Poison Resistance / Anti-Toxin: A creature that is resistant to poison or has taken an anti-toxin doubles the onset and escalation times, and never suffers more than 3 Fatigue from the poison.


Example
Standard Slow Poison (Injury Poison)

Onset: 1 minute
Medicine DC: 15
Escalation: 1 hour

A Con 16 Hero will take 1 fatigue after 4 minutes (1 +3 for con). 4 hours after that, they will take another fatigue. 4 hours after that, another fatigue. After a total of 20 hours and 4 minutes, the hero takes the final 6th fatigue and dies.
Heroic Save: Or, perhaps the hero was able to manage a long rest, recovering 1 fatigue. Ultimately when the poison finishes, the Hero has 5 fatigue, barely alive but not dead!

A Con 8 person will take 2 fatigue after 1 minute. 1 hour after that, they will take another 2 fatigue, etc. After 2 hours and a minute, the person takes their 6th fatigue and dies.

A Con 14 dwarf with poison resistance will take 1 fatigue after 6 minutes (1 + 2 con, x2). 6 hours after that, they will take 1 more fatigue, and another fatigue 6 hours after that. However, after 3 fatigue the poison ceases, as their poison resistance is able to flush out the poison.

The Slow Poisons (Could use Help with Pricing I'm spitballing right now)

Standard Slow (100 gp)
Onset: 1 minute
Medicine DC: 15
Escalation: 1 hour

Virulent (1000 gp)
Onset: 1 minute
Medicine DC: 18
Escalation: 30 minutes

 

[Dausuul]

I love the core idea--particularly using the exhaustion mechanic as a way to model the "death spiral" of poison, and the idea that this type of poison is inevitably fatal unless treated.

I do think the implementation is more fiddly than it needs to be. All you really need is a save DC (which doubles as the DC for Medicine checks) and a "speed setting."

• Instant poison: At the start of each of your turns, make a Constitution save. If you fail, gain a level of exhaustion.
• Swift poison: 1 minute after being poisoned, and each minute thereafter, make a Constitution save. If you fail, gain a level of exhaustion.
• Steady poison: 1 hour after being poisoned, and each hour thereafter, make a Constitution save. If you fail, gain a level of exhaustion.
• Slow poison: Each time you finish a long rest, make a Constitution save. If you fail, gain a level of exhaustion. This exhaustion cannot be removed until you are cured of the poison.

Also, it'd probably need be limited to humanoid targets, because otherwise it's way too easy to use it on monsters of animal intelligence. Anything which can't make a Medicine check, and can't get someone else to make a Medicine check for it, is doomed. This sort of poison is really designed to be used on the PCs rather than by them, but it's difficult to enforce such things.

 

[Stalker0]

I love the core idea--particularly using the exhaustion mechanic as a way to model the "death spiral" of poison, and the idea that this type of poison is inevitably fatal unless treated.

I do think the implementation is more fiddly than it needs to be. All you really need is a save DC (which doubles as the DC for Medicine checks) and a "speed setting."

• Instant poison: At the start of each of your turns, make a Constitution save. If you fail, gain a level of exhaustion.
• Swift poison: 1 minute after being poisoned, and each minute thereafter, make a Constitution save. If you fail, gain a level of exhaustion.
• Steady poison: 1 hour after being poisoned, and each hour thereafter, make a Constitution save. If you fail, gain a level of exhaustion.
• Slow poison: Each time you finish a long rest, make a Constitution save. If you fail, gain a level of exhaustion. This exhaustion cannot be removed until you are cured of the poison.

Also, it'd probably need be limited to humanoid targets, because otherwise it's way too easy to use it on monsters of animal intelligence. Anything which can't make a Medicine check, and can't get someone else to make a Medicine check for it, is doomed. This sort of poison is really designed to be used on the PCs rather than by them, but it's difficult to enforce such things.

You make a good point about monsters, so what I would probably do is add a clause that creatures with legendary resistance are immune from slow poisons. Regular monsters I have no issue with if a poison takes them out after a long period of time, if a party can spend the resource and wait that long, hey that's a reasonable tactic.

The main reason I went with the con=time component, is on one hand I am taking away the tough person's ability to just negate the poison like they can now, but I still wanted to give them back the "your constitution is very important in dealing with poison". The problem with a save is that con is only a minor component, even a low con person has a decent chance of making the save.

But saves are a well understood part of the system and your right it streamlines things. Further, it does give the creature a sense of "fighting the poison", even if ultimately they cannot stop it without some kind of aid.

I do want to keep the onset time, the classic fantasy trope is that a person starts "feeling the poison" pretty shortly after the injury, but then will often take a long time to die, so I think that extra complexity is useful (it also creates a dramatic tension for the first medicine check). Ok let me write up my own flavor of what you described and lets see how it looks.

 

[jgsugden]

Here is a quickie:

a.) The slow poisons have a Starting DC. These are about 3 higher than you'd expect. At low level they might be 15 to 17.

b.) The slow poison has a damage specified (like d8+4).

c.)The slow poisons have a 'Cycle' length (which could be minutes, 10 minutes, hours, days or something else).

When you reach a cycle period, you roll the saving through (usually Con) against the DC. If you succeed, the poison ends. If you fail, you:

1.) Take a level of exhaustion that can't be cured until the poison ends,
2.) You take the specified damage and reduce your maximum hps by that amount. That reduction remains until you take a long rest after the poison ends.
3.) Reduce the DC of the poison by 1 for future saves.

Removing the poison does not recover the body. You still have to rest to regain those HP, max HP and exhaustion levels.

A medicine check that beats the DC of the slow poison gives you advantage on the saving throw.

 

[Stalker0]

Slow Poison Alternate Version 1
Slow poisons take time to act but are exceptionally lethal. Without treatment, they are almost always fatal.

Onset: After this duration, the person makes a constitution saving throw equal to the poison DC. On a success, the duration resets. On a failure, the creatures takes 1 Fatigue and the poison moves into the Escalation phase.

Escalation: After this amount of time, the person makes a constitution saving throw equal to the poison DC and takes 1 fatigue on a failure. This repeats until the poison is cured or the target has made 10 saving throws (saves during onset do not count).

Medicine DC: A medicine check equal to the poison DC cures the poison if done during the onset period. During escalation, a successful check gives the creature advantage on their saving throws. A failed medicine check cannot be retried unless the healer gets access to new remedies or medicines.

Legendary Resistance: Creatures with legendary resistance cannot be affected by slow poisons.

Poisons
Slow
Onset: 1 minute
Escalation: 1 hour
DC: 15

Virulent
Onset: 5 rounds
Escalation: 30 minutes
DC: 18

Noxious
Onset: 1 round
Escalation: 1 minute
DC: 20

Example
A fighter gets hit with a slow poison. After 1 minute, they pass a constitution saving throw (DC 15). After an additional minute, they have to make another save and fail. They take 1 fatigue and now the poison is in escalation. 1 hour after that, they pass another save. 1 hour after that, they fail a save and take 1 fatigue. The process continues for an additional 8 more saves or until the poison is cured.

 

[Quickleaf]

Cool stuff. You're designing this for 5e, right?

It seems like the long onset time is at odds with lesser restoration or Lay on Hands (the cure poison use), unless you're using a whole bunch of monsters that can inflict poison or you're strictly sticking to adventuring days "full" of combats (i.e. to burn through spell slots/Lay on Hands in order to make the choice to cure poison an actual choice).

 

[Krachek]

You can use hit points maximum reduction.
if Initial save failed, then Your hit points maximum is reduce by X every Z minutes until neutralized or death whichever arrive first!
You adjust lethality with x and z.

 

[Stalker0]

It seems like the long onset time is at odds with lesser restoration or Lay on Hands (the cure poison use), unless you're using a whole bunch of monsters that can inflict poison or you're strictly sticking to adventuring days "full" of combats (i.e. to burn through spell slots/Lay on Hands in order to make the choice to cure poison an actual choice).

I wouldn't say they are at odds. Most 5e poisons are over too quickly for lesser restoration to see a lot of use. Either you pass the save and take no effect or you fail and take the big effect but you keep going. With slow poisons you are definately going to want to use a lesser restoration, for you know the pain is going to be great if you don't.

Also not all parties even with a cleric might have lesser restoration prepared in a given day, so now getting hit by a slow poison becomes a real ordeal....we either need to hold out through the night so the cleric can reprepare or find someone who can cast it (a classic fantasy trope of the hero that must survive through the night while under the effects of a deadly poison).

That to me is the rules working as intended. The goal is not to be killing players left and right with poison, the goal is to make it nasty enough that players will want to use their tools to get rid of poison or immediately begin looking for help.

 

[Stalker0]

So max hp reduction is certainly another way to do it, and like the others has its pluses and minuses. The nice thing about fatigue is its equally scary to lower and higher level people alike.... whereas 1d8 poison could be extremely nasty at low levels and barely an afterthought at high. On the other hand hitpoints already nicely model the effects of constitution and so we get a bit better balance there compared to saves which don't factor in con as much. So lets try a version with that.

Slow Poison Alternate Version 2 (Max HP)
Slow poisons take time to act but are exceptionally lethal. Without treatment, they are almost always fatal.

Poison Damage: Damage done by slow poison also reduces your maximum hp by the same amount. These hitpoints cannot be restored until the poison is cured. Once cured, a long rest is required to recover the missing hp.

Onset: After this duration, the person takes the listed poison damage. They then move into the Escalation phase.

Escalation: After this duration, the person takes the listed poison damage. This process repeats until the poison is cured.

Medicine DC: A medicine check equal to the poison DC cures the poison if done during the onset period. During escalation, a successful check gives the creature poison resistance. A failed medicine check cannot be retried unless the healer gets access to new remedies or medicines.

Legendary Resistance: Creatures with legendary resistance cannot be affected by slow poisons.

Poisons
Slow
Poison Damage: 1d8
Onset: 1 minute
Escalation: 1 hour
Medicine DC: 15

Virulent
Poison Damage: 2d6
Onset: 5 rounds
Escalation: 30 minutes
DC: 18

Noxious
Poison Damage: 1d8
Onset: 1 round
Escalation: 1 minute
DC: 20

Example
A fighter gets hit with a slow poison. After 1 minute, they take 1d8 poison damage. After an hour they take another 1d8 poison, continuing until they are cured or dead.

 

[Stalker0]

So far I think I'm liking Alternate Version 1 the best. I think its a good blend of simple but still hits the main tropes I am trying to hit with poison, and I think exhaustion just models the progression of poison better than max hp loss does. Any other thoughts?