Having poison require a 2nd favourable roll to work seems reasonable to me; not all "hits" are going to actually hit, or draw blood. D&D combat is more abstract, and HPs represent far more than just your physical sturdiness. Weapon damage is a reflection of the offensive capacity of the weapon, not just how dangerous it is once you have scored a "hit." (A spear is a dagger with greater reach - the blade is identical, yet the damage is increased to a D6. An open hand attack from a monk will never match a dagger for damage potential, except on bricks/planks of wood.)
Personally I dislike poison for the same reason I dislike guns and drum machines: it makes a mockery of hours/day/years of training to 'git gud.'
Or, to be more contemporary, when Batman is asked what his super power is, he replies "I'm rich." It's a joke of course, but all the best humour contains truth. (Not methane, that's not funny. Never was, never will be.)
Yes, yes, I know my argument falls down once you mention wands of fireball and Shardblades and Rings of Power that you win by knocking over a coconut...
So give heroes and villains a second opportunity to avoid a humiliating end writhing on the floor, tongue protruding, eyes bulging, bowels evacuating, convulsing like an '80s hip-hopper on acid.....it's just cheap (if you can afford it.)
If you are really into poisons in a gritty, fantasy setting, I highly recommend "Best Served Cold" by Joe Abercrombie. (Or do yourself a real favour and start with his "The Blade Itself: The First Law" - warning contains graphic torture and may not be suitable for all.)
Having poison require a 2nd favourable roll to work seems reasonable to me
Its more of a consistency / elegance thing. No other mechanic in the game requires two rolls like that. And, to be honest, its a bit annoying to have to separate the rolls and add more work - I prefer simple and elegant, and this feels rather clunky and fiddly. Its more of a design annoyance than anything. Its just annoying to have to roll to hit, then damage, then a separate check (also asking if target has resistance to poison), then damage again (also checking for resistance to poison). That's just a lot of extra annoying steps.
Or, to be more contemporary, when Batman is asked what his super power is, he replies "I'm rich."
The use of money to buy poisons is admittedly very odd. Mostly because, to be perfectly honest, the crafting and economic rules in 5e are kind of badly done. Normally, in most games, gold represents a separate XP track for the character (or, rather, the character's equipment). 5e steps away from that kind of economy, making gold rather meaningless save for a few nitpicks here and there. The various poisons are basically consumables on par with, say, a potion of haste. Rather than a potion, we have a powder that effectively casts sleep on the target. Which is another odd point - poisons aren't considered magical, despite coming from magical ingredients, but mithril armors are. Its oddly inconsistent point in world building.
I really feel like poisons weren't meant to be a PC thing. They were just added on as an antagonist thing - that's why they're in the DMG alongside diseases and traps.
I really feel like poisons weren't meant to be a PC thing. They were just added on as an antagonist thing - that's why they're in the DMG alongside diseases and traps.
The use of poison in D&D has traditionally always been seen as an evil act. Shakespeare didn't really help with that. (List it with his other crimes!)
Characters can't be shining examples if they use poison.
Oh, I'm not arguing that its "traditional." I'm arguing that its a bad fit in the current 5e paradigm. It could be streamlined much easier and effectively to work within the rules frame work better.
it seems like after the first few levels the usefulness of poisons dramatically fall off. Most poisons only have a DC 10-13 con saving throw .... so by level 5 or 6 most enemy creatures are more often the not making saving throw. Are we not understanding the rules of poison correctly ? does the poisoner's kit proficiency have anything to do with the potency of of the product?
Even so, those DC 10 saves can still be missed, and when they are, the poison (or whatever else they represent) has consequences. One of my players lost his 5th-level warforged warlock recently. He was attempting to cross a rope bridge. Moving at half speed and with a +3 to Acrobatics, a failure against DC 10 meant using all of his move and stopping. A failure by 5 or more resulting in the necessity of another DC 10 Athletics or Acrobatics check. He failed the first roll by rolling a '1' and the second by rolling a '5'.
Room 3 -Rift Hall, Forge of Fury. Although I increased the strength of the defenders, I left the bridge as conceived for 3rd-level adventurers and he still failed.
In the end, Cporter5, you can always homebrew (pun intended), poisons or anything else to make challenges easier or harder, depending on what you are looking to accomplish.
In the above example, I wanted the bridge to be easily crossed once they had eradicated the orc defenders (this party tends to rope themselves together - a sound tactic), but maintain some chance at peril if they attempted to cross while still engaged in melee. I weighed the small chance at peril against the party's known tendency of using caution. Leaving the bridge as written accomplished that, much to the chagrine of the warforged.
ok So I have just started to look into this. Poisons in 5th edition seem to suck. First off characters aren't necessarily good. Poisons are expensive on par with most magic weapons but their abilities are use once low DC. Low levels where they are most affective they cost too much to get. Yes it can be free damage but at current cost the amount of extra damage is not worth it. Uncommon magical items cost between 100-500g. that's a +1 weapon, a cloak of protection or a flying broom! or for a poison one use Basic poison (DC 10 for 1 min) Or Burnt Othur Fumes (DC 13 for three rounds). applying poison costs an action. Poisons should be scary and Dangerous but many spells make them trivial. remove poison (low level spell), Bless and many other spells give you advantage. Monsters make it tricky for the player because they don't have to pay for their poisons but for players it is usually not worth the money. Plus Poison is illegal in most places so you could get arrested for having it.
Yes Poison should be illegal, Yes poison should be resistible and curable but in my opinion their are too many defenses and not enough attack options for it which is sad
I usually up the DC and down the cost. A basic poison DC 12, 75g. Drow poison DC 14 120g etc. and then make sure that you can get in trouble for attacking or killing people with it. many monsters have poison immunity! reduce some of them to resistance. Poison should be used to effect the same way magic items do not only by monsters but by PC. they should be costly but not prohibitively. they have limited uses just like every other potion and Not easy to find usually you have to find someone shady for them
If you have a poisoner's kit and you're making poisons, the DC of those poisons should scale with proficiency. That's exactly the kind of thing proficiency is there for. At my table these kinds of half-baked systems just get tossed out completely and we homebrew it.
What 5e poisons really feels like to me is that they just wanted to lay down a framework that they could come back to later in something like Zehir's Noxious Notions, available now for 29.99!
Real world poison is all about secrecy, delay, and pain. You slip it into someone's body without them noticing it - food is the most common, but you have to despise the russian's with their umbrellas and their poison perfume sprayed on people. It kills days if not weeks later. It causes an incredible amount of extra pain. All of that should be illegal, it's either outright evil or an assassination attempt.
D&D poison is not that all. 95% of the time it's an add on designed to make a weapon attack more powerful. Sometimes it puts you to sleep WITHOUT killing you. Why would we outlaw that? D&D poisons are basically temporary +'s to your blade. If it is legal to carry a sword, it should be legal to apply a paralytic such as Carrion Crawler Mucus to it.
Also, there are several homebrew that list more poisons than the standard DMG stuff. No need to limit yourself.
Hmm yes and no. True some poisons can do that but their are also poisons meant for assassinations they deal poison damage or kill or cause blindness. which are not pleasant.
some of the poisons I could see being legal for medicinal use and I have done that in my games but their are poisons that are just nasty like in real life. Any poison that does damage I always describe as doing horrible things because that is what damage is. Poison can be a temporary boost to your sword or weapon but it can also be put in food or be inhaled or even used in a blow gun. Thus I would make a medical permit or something at least for some but as a general rule... poisons are bad unless you are very careful. even the ones that just put you to sleep could have bad effects or do so in a way that is dangerous similar to chloroform. its not illegal for science institutes or medical facilities but a normal person... illegal.
I think saves are really the only problem with poisons, the same could be said for magic saves in my opinion. You get pigeonholed into using the same abilities against certain enemies based on what saves you know they are weak to. To counter this, I propose the following:
If you don't possess an ability that makes you immune and you get hit with poison or some kind of other damage like a spell cantrip, you reduce damage to half right at the save threshold and reduce damage by another 10% for each point of save over the required. I would even go as far as applying this to duration spells with a negative effect. In the case of something like the spell Blindness/Deafness, you would just be checking if you get blinded for one round or not. If you fail a save that is DC 14(for example), you follow the normal spell rules. If you just make the save or are up to 19 as a result, you suffer 1 round of effect. 20 and higher is no effect.
That might be overcomplicated for some but, my experience with D&D saves is that players and even our DM, resort to using AOE and other abilities to force half damage. Save throws are too weak except, as someone mentioned, when an easy DC provokes a fluke fail result with disastrous consequences.
Sorry long time after to be replying, but I totally agree! I’m thinking since DC’s are anywhere from 10 to 14 depending on the poison just letting proficiency with poisoners kit add proficiency to the dc so or something. So a poisoners feature poison would be a DC 18 by 12th level. Yes this is high but Wizards spell save DC is like 17 by then anyway and most are either immune to poison or have incredibly high constitutions by then as well.
The main problem is that poison has a reputation for being super deadly and super evil. Oh no, he is poisoned, he can not be saved, he is going to die!
I would say that poisons could be a lot like spells in that you can always RESEARCH a better/higher level version if you put in the time, money and have the resources for the research. Research for spells was always a fun part of the early editions of D&D and can easily be used here. So the stock poisons only get you so far, then you'll have to do some "big boy" stuff to be effective later on.
Sorry long time after to be replying, but I totally agree! I’m thinking since DC’s are anywhere from 10 to 14 depending on the poison just letting proficiency with poisoners kit add proficiency to the dc so or something. So a poisoners feature poison would be a DC 18 by 12th level. Yes this is high but Wizards spell save DC is like 17 by then anyway and most are either immune to poison or have incredibly high constitutions by then as well.
You could certainly work it like spell DCs - 8 + int + prof bonus, say - but the big headache will be expertise, letting you reach save DC 25. Seperately, there will be concerns about a bunch of other abilities interacting (or not) with the save dc, like whether or not advantage on the poisoner's kit check should make the DC even bigger. And you haven't solved the problem of setting the poison's damage or the duration on its poisoned condition (if any) or any other poison effects.
The way ability checks are generally designed to work is you *beat* some DC to achieve some effect, so while it would be more work, I think the best homebrew for this just requires a table of poisons and their DCs to craft. A couple weeks ago I saw a very promising scheme posted that scaled the crafting DC based on factors like delivery vector, amount of damage, duration on certain conditions, save DC, and I think one or two others. It looked very well done, like it did a very decent job matching both the useless poison in the phb and the poisons in the dmg.
Logical Consistency: One of the issues with poisons is that if poisoning your weapon is super effective, then why doesn't everybody do it? Is using poison more dishonourable than incinerating or freezing someone to death? Is it really better than slicing their head off?
Game mechanic boredom: Poisons that only rely a creature to save vs. death are not fun. If your poison was highly reliable, then the go-to strategy becomes to poison every enemy to deal with them. This doesn't typically tie in with a fun game.
Balance: poison doesn't fall into a specific class remit, meaning that once you have a Poisoner among you, all of the characters in your group can use poison on their weapons. Effectively the whole party powers up to a level they aren't supposed to be at.
That said, as with all things 5e, talk to the DM and explain what you would like to create. I'm doing the same with Alchemy right now, allowing a Blood Hunter to craft all manner of cool stuff. He comes up with the idea, and I then come up with what he can make, and how he has to go about crafting it. There is a monetary cost, a time cost, and what he makes tends to be fun and situational rather than replacing his effectiveness in combat or outright boosting it. The game is not intended to be confined to the core rules alone - your DM is supposed to help you tell the story you want to tell, so ask and hopefully they're a good enough DM to want to help you realise some cool stuff.
I think poisons have high restrictions because they are so powerful. They do not factor into the CR equation for figuring out Challenge. They allow trading money and/or time crafting for Damage. There was a balance concern that needed to be addressed that's part of the reason so many creatures are immune to poison. At the same time many Iconic creatures are not immune Dragons, Vampires, Beholders. if you count holy water as a "poison for certain enemies" you have lots of options. There is a lot of misinformation about poisons and how they work. The basic Players hand book poison is weak but a review of the dmg poison section points out the true potential. Harvested poisons, truth serum, contact poisons all have huge potential. Harvested poisons have the most options because a player can save any poisonous creature'spoison. (wild shapes, polymorph and summons might be excluded due to magic)
From the DMG Crafting and Harvesting Poison (second paragraph)
A character can instead attempt to harvest poison from a poisonous creature, such as a snake, wyvern, or carrion crawler. The creature must be incapacitated or dead, and the harvesting requires 1d6 minutes followed by a DC 20 Intelligence (Nature) check. (Proficiency with the poisoner's kit applies to this check if the character doesn't have proficiency in Nature.) On a successful check, the character harvests enough poison for a single dose. On a failed check, the character is unable to extract any poison. If the character fails the check by 5 or more, the character is subjected to the creature's poison.
This gets particularly interesting with a PHB beastmaster who can order his pet to sleep/Unconscious. So In an hour they could attempt to harvest 10-60 Times. (realistically about 15-20). Many of the beast masters options also Have rider affects like Knocking them out until the poison condition is gone. Another interesting one is the Flying snake. A beastmaster adds damage to his companion's rolls. There is no save for the flying snake so the poison would get the extra damage because its the only roll as part of the attack. Giving you several uses of the Unique flying snake poison as free damage no save. Injury poisons, like the harvested flying snake, remain until they deal damage or are washed off. Please remember to share with the rest of the party (the ones who won't object because of Alignment/morals) for insane first round bonus damage.
Injury poisons, like the harvested flying snake, remain until they deal damage or are washed off.
Flying Snake poison appears to be Contact vector, like most natural poisons, because a target that resists all of the piercing damage (e.g. any raging barbarian) still takes the poison damage.
Just to be clear, a Ranger's bonus damage applies only to their companion's damage rolls. Someone else using the snake's poison would not get to add the Ranger's proficiency bonus. Whether said bonus will be forced to be piercing, poison, or Ranger's choice of damage type will be up to the GM, as that involves a rabbit hole so deep there's a thread about it right now over on the Rules & Game Mechanics forum that's reached page 8 with no sign of stopping, but in any case, it'll only apply when the snake rolls, not when anyone else rolls. Note that your interpretation of the word "roll" is widely accepted as incorrect - for example, a blowgun "rolls" 1d1 for rules purposes on every GM's table I've ever seen, rather than not getting a damage roll at all, which causes a variety of rules problems if you accept it.
Logical Consistency: One of the issues with poisons is that if poisoning your weapon is super effective, then why doesn't everybody do it? Is using poison more dishonourable than incinerating or freezing someone to death? Is it really better than slicing their head off?
Game mechanic boredom: Poisons that only rely a creature to save vs. death are not fun. If your poison was highly reliable, then the go-to strategy becomes to poison every enemy to deal with them. This doesn't typically tie in with a fun game.
Balance: poison doesn't fall into a specific class remit, meaning that once you have a Poisoner among you, all of the characters in your group can use poison on their weapons. Effectively the whole party powers up to a level they aren't supposed to be at.
That said, as with all things 5e, talk to the DM and explain what you would like to create. I'm doing the same with Alchemy right now, allowing a Blood Hunter to craft all manner of cool stuff. He comes up with the idea, and I then come up with what he can make, and how he has to go about crafting it. There is a monetary cost, a time cost, and what he makes tends to be fun and situational rather than replacing his effectiveness in combat or outright boosting it. The game is not intended to be confined to the core rules alone - your DM is supposed to help you tell the story you want to tell, so ask and hopefully they're a good enough DM to want to help you realise some cool stuff.
All these are reasons show why there are in game tools the dm can use to balance it out. Creatures immune to poison, A magic items that grant protection, Spells that allow benefits, Most poisons having low a dc, most of the rules are dm controlled not player controlled. (dm determines how hard it is to find crafting supplies or stock).
But in the end poisons are suppose to feel powerful and scary and cheap and dirty. Just like fireball is suppose to be iconically powerful even if the math doesn't match game standards.
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Having poison require a 2nd favourable roll to work seems reasonable to me; not all "hits" are going to actually hit, or draw blood. D&D combat is more abstract, and HPs represent far more than just your physical sturdiness. Weapon damage is a reflection of the offensive capacity of the weapon, not just how dangerous it is once you have scored a "hit." (A spear is a dagger with greater reach - the blade is identical, yet the damage is increased to a D6. An open hand attack from a monk will never match a dagger for damage potential, except on bricks/planks of wood.)
Personally I dislike poison for the same reason I dislike guns and drum machines: it makes a mockery of hours/day/years of training to 'git gud.'
Or, to be more contemporary, when Batman is asked what his super power is, he replies "I'm rich."
It's a joke of course, but all the best humour contains truth. (Not methane, that's not funny. Never was, never will be.)
Yes, yes, I know my argument falls down once you mention wands of fireball and Shardblades and Rings of Power that you win by knocking over a coconut...
So give heroes and villains a second opportunity to avoid a humiliating end writhing on the floor, tongue protruding, eyes bulging, bowels evacuating, convulsing like an '80s hip-hopper on acid.....it's just cheap (if you can afford it.)
If you are really into poisons in a gritty, fantasy setting, I highly recommend "Best Served Cold" by Joe Abercrombie. (Or do yourself a real favour and start with his "The Blade Itself: The First Law" - warning contains graphic torture and may not be suitable for all.)
Roleplaying since Runequest.
Its more of a consistency / elegance thing. No other mechanic in the game requires two rolls like that. And, to be honest, its a bit annoying to have to separate the rolls and add more work - I prefer simple and elegant, and this feels rather clunky and fiddly. Its more of a design annoyance than anything. Its just annoying to have to roll to hit, then damage, then a separate check (also asking if target has resistance to poison), then damage again (also checking for resistance to poison). That's just a lot of extra annoying steps.
The use of money to buy poisons is admittedly very odd. Mostly because, to be perfectly honest, the crafting and economic rules in 5e are kind of badly done. Normally, in most games, gold represents a separate XP track for the character (or, rather, the character's equipment). 5e steps away from that kind of economy, making gold rather meaningless save for a few nitpicks here and there. The various poisons are basically consumables on par with, say, a potion of haste. Rather than a potion, we have a powder that effectively casts sleep on the target. Which is another odd point - poisons aren't considered magical, despite coming from magical ingredients, but mithril armors are. Its oddly inconsistent point in world building.
I really feel like poisons weren't meant to be a PC thing. They were just added on as an antagonist thing - that's why they're in the DMG alongside diseases and traps.
The use of poison in D&D has traditionally always been seen as an evil act. Shakespeare didn't really help with that. (List it with his other crimes!)
Characters can't be shining examples if they use poison.
Roleplaying since Runequest.
Oh, I'm not arguing that its "traditional." I'm arguing that its a bad fit in the current 5e paradigm. It could be streamlined much easier and effectively to work within the rules frame work better.
Even so, those DC 10 saves can still be missed, and when they are, the poison (or whatever else they represent) has consequences. One of my players lost his 5th-level warforged warlock recently. He was attempting to cross a rope bridge. Moving at half speed and with a +3 to Acrobatics, a failure against DC 10 meant using all of his move and stopping. A failure by 5 or more resulting in the necessity of another DC 10 Athletics or Acrobatics check. He failed the first roll by rolling a '1' and the second by rolling a '5'.
Room 3 -Rift Hall, Forge of Fury. Although I increased the strength of the defenders, I left the bridge as conceived for 3rd-level adventurers and he still failed.
In the end, Cporter5, you can always homebrew (pun intended), poisons or anything else to make challenges easier or harder, depending on what you are looking to accomplish.
In the above example, I wanted the bridge to be easily crossed once they had eradicated the orc defenders (this party tends to rope themselves together - a sound tactic), but maintain some chance at peril if they attempted to cross while still engaged in melee. I weighed the small chance at peril against the party's known tendency of using caution. Leaving the bridge as written accomplished that, much to the chagrine of the warforged.
If recent UK news is anything to go by, the effectiveness of poison in 5th Edition is over-rated.
Roleplaying since Runequest.
ok So I have just started to look into this. Poisons in 5th edition seem to suck. First off characters aren't necessarily good. Poisons are expensive on par with most magic weapons but their abilities are use once low DC. Low levels where they are most affective they cost too much to get. Yes it can be free damage but at current cost the amount of extra damage is not worth it. Uncommon magical items cost between 100-500g. that's a +1 weapon, a cloak of protection or a flying broom! or for a poison one use Basic poison (DC 10 for 1 min) Or Burnt Othur Fumes (DC 13 for three rounds). applying poison costs an action. Poisons should be scary and Dangerous but many spells make them trivial. remove poison (low level spell), Bless and many other spells give you advantage. Monsters make it tricky for the player because they don't have to pay for their poisons but for players it is usually not worth the money. Plus Poison is illegal in most places so you could get arrested for having it.
Yes Poison should be illegal, Yes poison should be resistible and curable but in my opinion their are too many defenses and not enough attack options for it which is sad
I usually up the DC and down the cost. A basic poison DC 12, 75g. Drow poison DC 14 120g etc. and then make sure that you can get in trouble for attacking or killing people with it. many monsters have poison immunity! reduce some of them to resistance. Poison should be used to effect the same way magic items do not only by monsters but by PC. they should be costly but not prohibitively. they have limited uses just like every other potion and Not easy to find usually you have to find someone shady for them
If you have a poisoner's kit and you're making poisons, the DC of those poisons should scale with proficiency. That's exactly the kind of thing proficiency is there for. At my table these kinds of half-baked systems just get tossed out completely and we homebrew it.
What 5e poisons really feels like to me is that they just wanted to lay down a framework that they could come back to later in something like Zehir's Noxious Notions, available now for 29.99!
My homebrew subclasses (full list here)
(Artificer) Swordmage | Glasswright | (Barbarian) Path of the Savage Embrace
(Bard) College of Dance | (Fighter) Warlord | Cannoneer
(Monk) Way of the Elements | (Ranger) Blade Dancer
(Rogue) DaggerMaster | Inquisitor | (Sorcerer) Riftwalker | Spellfist
(Warlock) The Swarm
I disagree. I think D&D poison should be legal.
D&D poison is nothing like real world poison.
Real world poison is all about secrecy, delay, and pain. You slip it into someone's body without them noticing it - food is the most common, but you have to despise the russian's with their umbrellas and their poison perfume sprayed on people. It kills days if not weeks later. It causes an incredible amount of extra pain. All of that should be illegal, it's either outright evil or an assassination attempt.
D&D poison is not that all. 95% of the time it's an add on designed to make a weapon attack more powerful. Sometimes it puts you to sleep WITHOUT killing you. Why would we outlaw that? D&D poisons are basically temporary +'s to your blade. If it is legal to carry a sword, it should be legal to apply a paralytic such as Carrion Crawler Mucus to it.
Also, there are several homebrew that list more poisons than the standard DMG stuff. No need to limit yourself.
Hmm yes and no. True some poisons can do that but their are also poisons meant for assassinations they deal poison damage or kill or cause blindness. which are not pleasant.
some of the poisons I could see being legal for medicinal use and I have done that in my games but their are poisons that are just nasty like in real life. Any poison that does damage I always describe as doing horrible things because that is what damage is. Poison can be a temporary boost to your sword or weapon but it can also be put in food or be inhaled or even used in a blow gun. Thus I would make a medical permit or something at least for some but as a general rule... poisons are bad unless you are very careful. even the ones that just put you to sleep could have bad effects or do so in a way that is dangerous similar to chloroform. its not illegal for science institutes or medical facilities but a normal person... illegal.
agreed I Homebrew a lot of that stuff too and also take additional stuff of them net
I think saves are really the only problem with poisons, the same could be said for magic saves in my opinion. You get pigeonholed into using the same abilities against certain enemies based on what saves you know they are weak to. To counter this, I propose the following:
If you don't possess an ability that makes you immune and you get hit with poison or some kind of other damage like a spell cantrip, you reduce damage to half right at the save threshold and reduce damage by another 10% for each point of save over the required. I would even go as far as applying this to duration spells with a negative effect. In the case of something like the spell Blindness/Deafness, you would just be checking if you get blinded for one round or not. If you fail a save that is DC 14(for example), you follow the normal spell rules. If you just make the save or are up to 19 as a result, you suffer 1 round of effect. 20 and higher is no effect.
That might be overcomplicated for some but, my experience with D&D saves is that players and even our DM, resort to using AOE and other abilities to force half damage. Save throws are too weak except, as someone mentioned, when an easy DC provokes a fluke fail result with disastrous consequences.
Sorry long time after to be replying, but I totally agree! I’m thinking since DC’s are anywhere from 10 to 14 depending on the poison just letting proficiency with poisoners kit add proficiency to the dc so or something. So a poisoners feature poison would be a DC 18 by 12th level. Yes this is high but Wizards spell save DC is like 17 by then anyway and most are either immune to poison or have incredibly high constitutions by then as well.
The main problem is that poison has a reputation for being super deadly and super evil. Oh no, he is poisoned, he can not be saved, he is going to die!
The game is just not designed to do that.
I would say that poisons could be a lot like spells in that you can always RESEARCH a better/higher level version if you put in the time, money and have the resources for the research. Research for spells was always a fun part of the early editions of D&D and can easily be used here. So the stock poisons only get you so far, then you'll have to do some "big boy" stuff to be effective later on.
Pallutus
You Quote from Harbinger_Ajax >>
You could certainly work it like spell DCs - 8 + int + prof bonus, say - but the big headache will be expertise, letting you reach save DC 25. Seperately, there will be concerns about a bunch of other abilities interacting (or not) with the save dc, like whether or not advantage on the poisoner's kit check should make the DC even bigger. And you haven't solved the problem of setting the poison's damage or the duration on its poisoned condition (if any) or any other poison effects.
The way ability checks are generally designed to work is you *beat* some DC to achieve some effect, so while it would be more work, I think the best homebrew for this just requires a table of poisons and their DCs to craft. A couple weeks ago I saw a very promising scheme posted that scaled the crafting DC based on factors like delivery vector, amount of damage, duration on certain conditions, save DC, and I think one or two others. It looked very well done, like it did a very decent job matching both the useless poison in the phb and the poisons in the dmg.
Logical Consistency: One of the issues with poisons is that if poisoning your weapon is super effective, then why doesn't everybody do it? Is using poison more dishonourable than incinerating or freezing someone to death? Is it really better than slicing their head off?
Game mechanic boredom: Poisons that only rely a creature to save vs. death are not fun. If your poison was highly reliable, then the go-to strategy becomes to poison every enemy to deal with them. This doesn't typically tie in with a fun game.
Balance: poison doesn't fall into a specific class remit, meaning that once you have a Poisoner among you, all of the characters in your group can use poison on their weapons. Effectively the whole party powers up to a level they aren't supposed to be at.
That said, as with all things 5e, talk to the DM and explain what you would like to create. I'm doing the same with Alchemy right now, allowing a Blood Hunter to craft all manner of cool stuff. He comes up with the idea, and I then come up with what he can make, and how he has to go about crafting it. There is a monetary cost, a time cost, and what he makes tends to be fun and situational rather than replacing his effectiveness in combat or outright boosting it. The game is not intended to be confined to the core rules alone - your DM is supposed to help you tell the story you want to tell, so ask and hopefully they're a good enough DM to want to help you realise some cool stuff.
I think poisons have high restrictions because they are so powerful. They do not factor into the CR equation for figuring out Challenge. They allow trading money and/or time crafting for Damage. There was a balance concern that needed to be addressed that's part of the reason so many creatures are immune to poison. At the same time many Iconic creatures are not immune Dragons, Vampires, Beholders. if you count holy water as a "poison for certain enemies" you have lots of options. There is a lot of misinformation about poisons and how they work. The basic Players hand book poison is weak but a review of the dmg poison section points out the true potential. Harvested poisons, truth serum, contact poisons all have huge potential. Harvested poisons have the most options because a player can save any poisonous creature's poison. (wild shapes, polymorph and summons might be excluded due to magic)
From the DMG Crafting and Harvesting Poison (second paragraph)
A character can instead attempt to harvest poison from a poisonous creature, such as a snake, wyvern, or carrion crawler. The creature must be incapacitated or dead, and the harvesting requires 1d6 minutes followed by a DC 20 Intelligence (Nature) check. (Proficiency with the poisoner's kit applies to this check if the character doesn't have proficiency in Nature.) On a successful check, the character harvests enough poison for a single dose. On a failed check, the character is unable to extract any poison. If the character fails the check by 5 or more, the character is subjected to the creature's poison.
This gets particularly interesting with a PHB beastmaster who can order his pet to sleep/Unconscious. So In an hour they could attempt to harvest 10-60 Times. (realistically about 15-20). Many of the beast masters options also Have rider affects like Knocking them out until the poison condition is gone. Another interesting one is the Flying snake. A beastmaster adds damage to his companion's rolls. There is no save for the flying snake so the poison would get the extra damage because its the only roll as part of the attack. Giving you several uses of the Unique flying snake poison as free damage no save. Injury poisons, like the harvested flying snake, remain until they deal damage or are washed off. Please remember to share with the rest of the party (the ones who won't object because of Alignment/morals) for insane first round bonus damage.
Flying Snake poison appears to be Contact vector, like most natural poisons, because a target that resists all of the piercing damage (e.g. any raging barbarian) still takes the poison damage.
Just to be clear, a Ranger's bonus damage applies only to their companion's damage rolls. Someone else using the snake's poison would not get to add the Ranger's proficiency bonus. Whether said bonus will be forced to be piercing, poison, or Ranger's choice of damage type will be up to the GM, as that involves a rabbit hole so deep there's a thread about it right now over on the Rules & Game Mechanics forum that's reached page 8 with no sign of stopping, but in any case, it'll only apply when the snake rolls, not when anyone else rolls. Note that your interpretation of the word "roll" is widely accepted as incorrect - for example, a blowgun "rolls" 1d1 for rules purposes on every GM's table I've ever seen, rather than not getting a damage roll at all, which causes a variety of rules problems if you accept it.
All these are reasons show why there are in game tools the dm can use to balance it out. Creatures immune to poison, A magic items that grant protection, Spells that allow benefits, Most poisons having low a dc, most of the rules are dm controlled not player controlled. (dm determines how hard it is to find crafting supplies or stock).
But in the end poisons are suppose to feel powerful and scary and cheap and dirty. Just like fireball is suppose to be iconically powerful even if the math doesn't match game standards.