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Zazamori
2019-08-10, 08:31 PM
I'm relatively new to D&D as whole, but I'm quickly discovering homebrewing is one of the most entertaining aspects of the game for me. I like to find holes the official material left wanting & fill them. However, given my inexperience, I am often quite worried about balance. I suspect I may have a tendency to over-do things. I also may not have adept enough lore knowledge or even creativity for flary flavor text. Feedback & suggestions are definitely appreciated.

My main character lately has a thing for poisons. He really like to milk the devil's utters. Like everyone else, I've realized the official rules for crafting poisons are, ahem, not there. I've found numerous fantastic homebrews that fill in that blank as far as brewing poisons from plant ingredients is concerned. However, I also find the official rules for extracting creature poisons to be limiting & difficult to work with; a comprehensive guide for fixing that seems more elusive.

To recap: As far as I'm aware, the only official rules for extracting & using extracted poisons are basically:
1) DC 20 Int (Nature) check for all extractions
The venomous creature from which the poison is being extracted must be incapacitated or recently deceased.
Can add Poisoner's Kit proficiency if lacking Nature proficiency.
I believe there's an optional rule (I think in XGtE?) that states to take advantage if you have proficiency with both a relevant skill & relevant tool for the same check, which could easily be considered here.
2) Produces a single dose on success, none on failure.
Poisons the character attempting the extraction if failed by 5 or more
XGtE Poisoner's Kit description vaguely suggests that having the kit may mean you won't accidently poison yourself on a -5 failure, but debatably only means you won't poison yourself when using poisons you've already placed in vials. I find the latter interpretation more fun.
3) Based on the DMG example poisons, it seems implied that any poison extracted this way will have the same affects for you as it does for the creature on an attack for attack basis.
Probably any creature extracted poison I can think of is an Injury style application by default.
4) A single vial of Injury poison contains a single dose.
A single dose of poison can be applied to 3 pieces of ammo or 1 piercing/slashing weapon.
Takes an action to apply.
Must be used within 1 min or it dries out & loses potency.
Per Errata, if a successful attack is made with a poison weapon, the poison comes off in the wound. The blade is no longer poisonous.
Any damaging effects are dealt once upfront, not per round.

I included the rules about using injury poisons just as a baseline reminder of how limiting the official system is.


I've decided to take a crack at revamping this system to be more workable.
Some concerns I intend to address include:
1) Different creatures should have different poison extraction difficulties.
2) Different creatures should yield different amounts of poison.
3) Cooperative animal friends, such as familiars, ought to be able to willing donate poison without being incapacitated & while making the process easier for the extracting character.
4) Even during an accidental exposure, I think it's reasonable to assume you were being careful enough to avoid a FULL dosing.
5) A wider variety of abilities & skills ought to be useable to make it more widely accessible.

So, I'll actually start with the last enumerated concern first. I think there should be a little freedom in choosing which skill is applicable for poison extraction checks. Int (Nature) as in the DMG is sensible, but I would also want to say that Wisdom (Medicine) should be an acceptable alternative. Afterall, the difference between medicine & poison is dosage. Plus, medicine skill could mean a character could have anatomical knowledge, much of which may even be vaguely transferable between species, & could assist with slicing out a venom sac/duct/gland. I also see no reason that Wisdom (Nature) or Intelligence (Medicine) shouldn't work if you've got one of those unusual combos going for some reason. This opens up safely extracting poisons to a lot more characters. I would say that alone is sufficient, but if we want to go a little crazier, we might say Dexterity (Nature) or Dexterity (Medicine) could be used, since being good with your hands could mean you have a greater ability to perform precision gestures &/or slices while avoiding mistakes. I DON'T think Dexterity (Sleight of Hand) seems acceptable since anatomical knowledge should be involved. If the creature is alert & willing, Wisdom (Animal Handling) could also make sense & not necessarily require anatomical knowledge on your part since the creature knows its own body & is doing what it can to help you.


Secondly, I think it's reasonable for creatures to potentially yield multiple doses of poison since they can bite/sting/claw you for multiple doses during a single combat. Larger creatures should have larger amounts of poison. A simple assortment could be starting at 1 & increasing by 1 die size per creature size category.
Tiny - 1 dose
Small - 1d4 doses
Medium - 1d6 doses
Large - 1d8 doses
Huge - 1d10 doses
Gargantuan - 1d12 doses
Colossal - 1d20 doses
Pretty sure some of these size categories may not include any official poisonous creatures, but it's there.
I think it would also be reasonable to say that if the creature used it's poison X many times during the fight to subdue/kill it, you can subtract that amount from the harvestable doses, potentially resulting in zero yield.
If you extract poison from a creature while leaving it alive, it is assumed you took all the poison available for you to extract & no more can be harvested from that particular creature for awhile. It will generate new poison at a rate of 1d4 doses per long rest up to the max allowed by its size. This way you can't endlessly milk your jellyfish familiar.


Thirdly, I'm thinking of basing extraction difficulty on a combination of a creature's liveliness, willingness, & challenge rating (rounded up to nearest whole).
Incapacitated Creature Extraction DC: 18 + CR + Con mod (min 0)
Dead Creature Extraction DC: 14 + CR
Willing Creature Extraction DC: 10 - creature's Wis or Int mod, whichever is higher, negatives allowed

For example, extracting poison from a Giant Toad will have a DC 20 (= 18 + 1 CR + 1 Con) if its incapacitated, DC 15 (= 14 + 1 CR) if it's dead, & DC 10 (= 10 - 0 Wis) if it's a willing donor. Meanwhile, extracting the famous Purple Worm Poison would have a DC 39 (= 18 + 15 CR + 6 Con) if its incapacitated, DC 29 (= 14 + 15 CR) if its dead, or DC 11 (= 10 - [-1 Wis]) if it's willing. Since you probably won't find a Purple Worm looking to give away it's venom, this actually makes it a lot harder to get poison from it than using the DMG rules, but when you do, you may end up with significantly more poison, since it is a gargantuan creature (1d12 - uses during fight). However, much weaker creatures will tend to be significantly easier to milk than per DMG rules. Of course, your supply will still be limited by the number of creatures available.

The strongest poisonous creature I know of would be an Ancient Green Dragon. Using the above calcs, getting poison from it would require beating DC 47 (= 18 + 22 CR + 7 Con) if it's incapacitated, DC 36 (= 14 + 22 CR) if it's dead, & DC 5 (= 10 - 5 Int) if it's a willing donor. 2 thing to notice about this:
1) It's easier to get poison from a willing ancient green dragon than from a willing creature that's, ahem, less gifted. Because it's so smart, it would have no problem simply spitting it's own poison out for you to collect, if it wanted to do that.
2) Since it will probably almost never want to do that, you would have to take it's incredibly poisonous poison by force, which is borderline impossible at the given difficulties. This keeps a stupidly powerful poison out of the hands of feeble mortals.



...unless I take this opportunity to introduce a homebrew magic tool kit!! I posted another thread in these forums recently asking why (among other things) +1/+2/+3 magic tools don't seem to exist. I haven't since been given any compelling answer why they shouldn't. So I've included that, but also thunk up some additional perks.

*insert famous lore poisoner character name here*'s Kit of Untimely Ends (obviously open to suggestions)
Poisoner's Kit, Legendary, (Should it require attunement? I'm leaning towards nah.)

Although she would never have admitted it to just anyone, it's rumored this kit was designed by the infamous Drow assassin, --, for the purpose of harnessing & wielding even the deadliest poisons from the least acquiescent of monsters. Although this kit is most likely a replica, it's said that -- once used a kit such as this to successfully harvest poison from a still-living ancient green dragon. For surely unrelated reasons, *Insert political enemies name* of the rival *insert faction name* House mysteriously perished three days later, slouched on her throne; a tiny tack carelessly left on the seat was the closest thing to a murder weapon that could be identified. Just a coincidence...surely.
In addition to containing exquisitely crafted versions of the normal components of a poisoner's kit, this kit contains a magic scalpel that functions as a divining rod for poisons, allowing you to better know where a creature stores its poison & make more precise slices while extracting it, reducing risk of spillage. It also comes equipped with a limitless supply of magical sedatives, analgesics, & administration equipment which you may use to force incapacitated poisonous creatures to become more compliant. Like a normal poisoner's kit, this kit holds up to 10 vials, but any vial used to store poison in this kit gains the magic property to hold triple the amount of poison as a regular vial (3 rather than 1). Poisons stored in these vials never expire.

Add +3 to any ability check made to brew or extract a poison using this tool. *This may be too much. Considering removing it*
Vials in this kit can hold up to 3 doses of poison each. All doses of a poison stored within a single vial must be the same poison.
For the purpose of poison extraction, you can choose to halve the CR component of the DC (rounded down), but if you do, the amount of poison obtained is reduced by half (rounded down).
You have a +2 bonus to the DC to identify or resist the effects of any poison applied or administered using this kit.
*Probably something to benefit plant-based poisons. Should synergize with an herbal poison guide. Will decide specifics later.*
*Open to adding more perks, taking suggestions. I want to ultimately make this worthy of a Legendary rank, I don't feel it's quite there yet.*


There could also be weaker, but similar versions at lower rarity tiers.

Revisiting the Ancient Green Dragon using this tool, the DCs could now be DC 36 (= 18 + 22 CR / 2 + 7 Con) for incapacitated & DC 25 (= 14 + 22 CR / 2) for dead. What was once impossible is now within reach, but only for a poisoner in possession of this legendary item. For those keeping score, our poison extraction bonus could be +5 from relevant ability score, +6 from proficiency, +3 from this magic tool, for a total of +14. Assuming I've mathed correctly, that's a 0% chance of succeeding on extracting poison from a live ancient green dragon with an 85% chance of being poisoned in the process & 50% chance of succeeding on a dead one with a 30% chance of being poisoned. It's reasonable to assume that the dragon used it's breath weapon at least once during the fight to subdue it, leaving (1d12 - 1) / 2 potential doses to be obtained from this extraction. That's a maximum of 5 doses, but possibly still as low as zero. I would like input on whether or not that reward is worth the risk. Adding in Expertise, Guidance, Bardic Inspiration, player ability scores in excess of 20, spells or something to nerf greeny's Con (does that exist?), or another similar effect could improve the odds & even make it just barely possible to get it from a live ancient green, if for some reason you need to do it that way.


Winding down with a simple bit, I think it reasonable to say that a character being careful in their poison extraction attempt is more likely to get only a tiny exposure than a full dose upon accidental injury. I think it could be reasonable to say:
Failing the ability check by 5-9 or more results in accidental poisoning of yourself in which you automatically succeed on any saving throws induced by the poison.
Failing by 10-14 or more results in suffering the full effects of the poison, including making normal saving throws.
Failing by 15 or more means you made an exceptionally clumsy mistake resulting in automatic failure of the saving throws.
Failing by 20 or more means you're in way over your head with no idea what you're doing & absolutely messed up royally resulting in taking the full effects of the poison as if you were struck with it twice. You should probably not play with poisons ever again. I doubt failing by 20 or more could reasonably happen to a character with any sort of caution, but wouldn't that be silly.

I will stop here for now. If this isn't torn to shreds, the future could hold a reformatting for better organization/flow, integration with existing homebrew herbal poison rules with ability to modify creature poisons by brewing in recipe with plant stuff, rules for mixing, concentrating, or diluting poisons, & possible expansion to other stuff like extracting acids, other breath weapon essences, or similar things, although those may be the domain of an alchemy kit more than a poisoner's kit.

Edit:
Adjusted DC. Since I've apparently decided ancient green dragon poison is the standard of a nearly unobtainable poison, I want it to be a hair out of reach to take from a live critter unless the stars align & even fairly dangerous to take from a dead one. Upped the DCs to reflect that. I also reckon I like that difficulty increase even on the low end. A simple poisonous snake still won't be as tricky to harvest as per DMG rules, but I want having at least one profeciency to be essential to harvesting reliably and competently even from easy critters.

Edit 2:
Modified tool.

Zhorn
2019-08-10, 10:49 PM
Was having a similar discussion int eh 5e thread, though I was looking at it from a minimal tweak of the core rules rather than a full on homebrew overhaul.
In any case;
http://www.giantitp.com/forums/showthread.php?594758-Poisoner-s-kit-harvesting-venom
Feel free to take of the advice given by the responders or ideas I was throwing about and use them as you like, or build a better mouse trap :smallwink:

Zazamori
2019-08-11, 01:40 AM
Ummmm, having now read your thread, I feel like I just ripped off your ideas. Somewhat discouraging, I must not be as original as I thought. But also perhaps encouraging to think it must be decent if someone else got there too. I definitely appreciate your referal. Thanks, Zhorn!!

Zhorn
2019-08-11, 02:13 AM
Don't feel like it's ripping off an idea. We're both coming at it from a pre-existing game system. Originality needn't be a concern.


On the topic of mechanics;

DC:
Like what Fable Wright responded with in my thread, consider what DC your check is going to get up to with the formula you are choosing. While we are in disagreement on what the number range should be, it doesn't make their point any less valid on keeping those numbers within the scope of the bounded accuracy of 5e's system.

Complexity:
I like the direction you are taking your formula, but I do worry about the number of parts it's using to get there. Fortunately it is not an equation that will need to be worked out multiple times over an encounter, but anything more than a single operation is going to creep out of that on-the-fly simplicity that keeps pen&paper games accessible.

Valid Targets:
This is much of a muchness, but green dragon poison doesn't strike me as something that would fit into the viable weapon poison category, since it's a breath weapon and described as a poisonous gas. Unless you're looking at it as an inhale type, but you may still need to think of harvesting and delivery methods of gas poisons.

Zazamori
2019-08-11, 03:41 AM
DC:
Like what Fable Wright responded with in my thread, consider what DC your check is going to get up to with the formula you are choosing. While we are in disagreement on what the number range should be, it doesn't make their point any less valid on keeping those numbers within the scope of the bounded accuracy of 5e's system.

I realize the formulas allow for absurdly high DCs. On one hand, it seems silly to even put in an impossibly high DC. On the other hand, I like the idea of the strongest poisons being off limits to all but the most well-equipped & skilled & fortunate.
This also made it relatively easy to come up with a main property for the magic tool I wanted to make anyway, in bringing those impossible DCs back down into possible ranges. I see why it could be troublesome that thr item can work in a vacuum. The system is silly without the tool & the tool is unnecessary in a different system. I ultimately want to think up magic tools of every sort (with more creative buffs than the simple +#), but I want them all to be useful even without new rule sets to make them work.


Complexity:
I like the direction you are taking your formula, but I do worry about the number of parts it's using to get there. Fortunately it is not an equation that will need to be worked out multiple times over an encounter, but anything more than a single operation is going to creep out of that on-the-fly simplicity that keeps pen&paper games accessible.

Yes, this has occurred to me. I figure at least all the info one requires can be found together on one page of a book, app, website, or what-have-you. If you need to look up the CR, you're bound to find ability scores right there with it. Those folks who don't enjoy the complexity can simplify to something like willing creature = autopass & a single formula for anything else. I may explicitly add the caveat that the incapacitated-dead distinction is optional. However, personally, I enjoy the tad more complexity & I can conceptualize numerous reasons to justify the difficulty tiers I've selected.


Valid Targets:
This is much of a muchness, but green dragon poison doesn't strike me as something that would fit into the viable weapon poison category, since it's a breath weapon and described as a poisonous gas. Unless you're looking at it as an inhale type, but you may still need to think of harvesting and delivery methods of gas poisons.

I was imagining it could be used as an injury poison, but now that you mention it, I suppose it ought to also work as an inhalation in a pinch.
I have so far chosen to believe the essence of a dragon's breath weapon is stored in a liquid state in a specialized sac inside the body (assuming it isn't purely magical). Something about the dragon's biology allows it to aerosolizes as it's emitted. I've pictured it as a spray of aerosolized droplets rather than purely a gas. It's easy for a liquid to maintain its direction and speed through a gas medium (air), whereas one gas would have a more difficult time maintaining a steady streaming flow through another gas. I don't know the lore in enough depth to be certain any of that is right.
I reckon it could also be that the alchemical environment inside the dragon's poison sac maintains it in liquid form and it rapidly evolves into a gaseous state when exposed to air.
Either way, I have no doubt I've thought about it more than I was ever supposed to.

Zhorn
2019-08-11, 05:08 AM
Run with what you like the most.
A high DC is fine as long as it is well reasoned why it's that high.
Personal opinion would be DC 30 is where you'd want to consider if the check is set too high or not for what it is achieving, but how soon you get there will depend on what creature's poisons you consider fair game to harvest.

Like you, I'd consider green dragon's breath weapon poison to be deployed more like an aerosol, being in liquid form in glands until it is being deployed. But I would also view it as a fast-vaporising substance once exposed to air, making it hard to extract into a container. This is just me though.

The most deadly poison my players would likely deal with is going to be purple worm poison, which outside of green dragon breath weapons is the most potent. Under my setup that comes out at DC 28 (13 + CR), under your's...
CR: 15, Con: +6

Without the tool:
Incapacitated Creature Extraction DC: 18 + CR + Con mod (min 0): DC 39
Dead Creature Extraction DC: 14 + CR: DC 29
Willing Creature Extraction DC: 10 - creature's Wis or Int mod, whichever is higher, negatives allowed: DC 11 or 15

With the tool:
Incapacitated Creature Extraction DC: 18 + CR / 2 + Con mod): DC 28 or 29
Dead Creature Extraction DC: 14 + CR / 2): DC 21 or 22


Where that DC 39 is the only part I feel is too high. Everything else the only issue I see is the steps needed to arrive at the numbers.

BerzerkerUnit
2019-08-11, 03:38 PM
My rules for ease of play:
Poisoner’s Kit DC equals Save DC of the Poison (20 if there is no DC) for 1 dose.
You can get additional doses for every 5 you exceed the DC.

You can use an Alchemist Or Herbalism Kit but if you fail the check by more than 5 you poison yourself.