Kobold Think Tank
Tabletop RPG advice for little dragons

Deadly Poisoner Builds in DnD 5e

by Brandon Gregory

Illustration of a goblin rogue holding a dagger and some vials of poison

Poison is an iconic part of the Medieval combat fantasy that can be a fun part of a character, but poison in DnD 5e is a bit of a mixed bag. How do you make a character who can reliably use poison in their attacks? Is poison even worth using? What classes and subclasses will work best for a poisoner build?

A poisoner character can be a fun and effective in most situations, but there are some caveats to be aware of. This guide covers the efficiency of poison damage in 5e and considerations for building a poisoner-type character.

Contents
  1. The Poisoner Feat
  2. The State of Poison Damage in 5e
    1. Poison Resistance and Immunity - All Monsters
    2. Poison Resistance and Immunity by Creature Type
    3. Poison Resistance and Immunity - Low-Level Monsters
    4. Is Poison Damage Bad?
  3. Being an Efficient Poisoner
  4. Best Classes and Subclasses for Poisoner Characters
  5. Classes to Avoid for Poisoner Characters
  6. Poisoners Without the Poisoner Feat
  7. What About Other Poisons?

The Poisoner Feat

The key to a real poison-themed character is the Poisoner feat from Tasha’s Cauldron of Everything. This feat grants several benefits, most notably allowing you to ignore poison resistance on creatures and create several doses of a potent poison that can increase damage with weapon attacks. You don’t get unlimited poison, but you can choose when to apply it to your weapons, requiring some strategy on when to try for that damage boost.

The poison also causes the poisoned condition for a short time. Poisoned is a nasty condition that imposes disadvantage on all attack rolls and ability checks, which can debilitate some foes.

Bear in mind that the additional poison damage and the poisoned condition rely on the target failing a relatively low Constitution saving throw, so huge monsters, which likely have a high Constitution, aren’t great targets for your poison. Enemy spellcasters can be easier targets, but if you don’t have one of them to focus on, you might have better luck using your poison to quickly take out the weaker foes that often accompany huge monsters.

The State of Poison Damage in 5e

Poison is an iconic way to kill someone with a long history in DnD, but the mechanics of 5e present us with a mixed bag. The various damage types are all balanced, so the easier it is to get a damage type, the more creatures have resistance or immunity; poison is the most common damage type, which means it has the most creatures with resistance or immunity. The Poisoner feat allows you to ignore resistance to poison damage, which is a nice perk, but it doesn’t solve the problem of poison immunity.

As of Keys from the Golden Vault, here are the stats on creatures with resistance or immunity to poison damage.

Poison Resistance and Immunity - All Monsters

A whopping 25% of monsters are immune to poison damage, and the Poisoner feat won’t help with that. To compare with the next most resisted damage type, fire damage, here are the stats for that:

So for poison, compared to other damage types, resistance is less of a problem, but immunity is more of a problem. Ignoring poison resistance is still a nice perk, but it’s not as meaningful as it would be for another damage type.

Poison Resistance and Immunity by Creature Type

Creature type also plays a big role in poison considerations. Most poison immunities come from 3 monster types: Constructs, Fiends, and Undead. Knowing what type of monsters you’ll be facing can greatly improve the effectiveness of poison. Here’s a breakdown of all the creature types and how many of that type are immune to poison damage:

Poison Resistance and Immunity - Low-Level Monsters

The numbers above are for the entire spectrum of monsters, which goes up to CR 30. Most adventures and campaigns take place at lower levels. So if we limit our stats to creatures that are CR 8 or under, the stats for poison immunity improve a bit:

Is Poison Damage Bad?

As mentioned above, the damage types are balanced, so no damage type is bad—it’s all about risk versus reward. Poison immunities are much more common than with other damage types, but there also aren’t feats that can grant you an additional 2d8 damage per turn with other damage types.

A character built around poison damage is more of a high-risk, high-reward style of play—you’ll get more damage most of the time (high-reward), but there will be times when that advantage is nullified (high-risk). If you want consistent, reliable damage, poison probably isn’t for you. If you like having a wildcard that sometimes gives you an advantage, a poisoner build can be a great fit.

Being an Efficient Poisoner

With the Poisoner feat, you only get a few uses of your potent poison per day, and wasting one of them is not a great feeling—you want to make them count.

Ranged attackers run the risk of applying the poison to their ammunition and then missing, wasting that use of the poison. If you want to be a ranged poisoner, you need to boost your accuracy to make sure you’re not throwing away that damage boost. The Archery fighting style is a great way to boost your accuracy, so Fighters and Rangers can make great poisoners. If a character has a reliable way of getting advantage on attacks, this can work too. Other boosts, such as the War Cleric’s Channel Divinity or the Kensei Monk’s various ranged features, can work as well. Just try not to miss.

Ranged attackers do get a benefit to balance this weakness, though: they’re much more capable of choosing the most vulnerable target. While a melee attacker might get stuck fighting the front-line enemies, a ranged attacker can easily target the enemy mages or archers in the back line. This can make a major difference, as front-line attackers are more likely to have better Constitution saves, making it harder to apply your poison.

For melee attackers, there’s less risk with accuracy—you apply the poison to your weapon, and as long as you can land a hit within 1 minute, the poison hits the target. Despite this protection, improving your accuracy enables you to get more hits with your poison in. Getting advantage on your attacks, such as with a Samurai Fighter’s Fighting Spirit or a Barbarian’s reckless attack, can boost the efficiency of your poison damage.

For either melee or ranged attackers, the poison only works if the target fails a Constitution saving throw with a set DC, so making a target worse at Constitution saving throws can greatly boost your efficiency. Here are some spells and abilities that can help with that:

Note that these spells and abilities are not likely to be available to martial characters, so you may need to coordinate with your party. You can make this more beneficial for the team by having other party members use spells or abilities that require a Constitution saving throw, such as the Monk’s Stunning Strike or spells like Blindness/Deafness and Shatter, or even the Poison Spray cantrip if you want to go all in on poison damage.

Best Classes and Subclasses for Poisoner Characters

Barbarian - Ancestral Guardian

The ability to attack recklessly makes Barbarians great melee poisoners, and the only class feature that uses their bonus action is Rage, which is typically only used once per fight. Ancestral Guardians have little synergy with poison, but there’s no conflict either.

Barbarian - Totem Warrior

Much like the Ancestral Guardian, Totem Warriors have little conflict with the Poisoner feat, and the base Barbarian features like Reckless Attack make them great melee poisoners.

Cleric - Trickery Domain

Clerics aren't known for their weapon attacks, but Trickery Domain Clerics have some useful features that make them decent archers as well as tricksters. What makes them a good fit for a poisoner, though, is that they already get poison damage—at level 8, they can add poison damage to their weapon attacks. Overcoming resistance to poison is a minor perk, but it's still a good perk for a class that deals poison damage anyway. If you want to go all-in on poison, Trickery Clerics let you double up on it.

Fighter - Arcane Archer

Arcane Archers gain access to the Archery fighting style to boost their accuracy and also get Curving Shot, which means more of your poisoned arrow hit. Their bonus action is usually available to apply the poison as well.

Fighter - Battle Master

Battle Masters also get access to the Archery fighting style, but can easily use melee if needed. Most Battle Master maneuvers leave the bonus action open to apply poison.

Fighter - Champion

Champions have no conflict with the Poisoner feat. Since the poison requires a saving throw, it's not technically part of the attack you make, so it does not get critical hits along with your weapons. This was confirmed by lead game designer Jeremy Crawford. Still, if you’re looking for a basic Fighter class that uses poison, this will work.

Fighter - Samurai

Samurai are great with both bows and great weapons and can boost their accuracy with either weapon by using Fighting Spirit, but Fighting Spirit uses their bonus action, so they can't apply the poison and boost their accuracy on the same turn. Still, Samurai are great at many combat-related tasks, and having an extra tool like poison in your repertoire can be beneficial.

Ranger - Fey Wanderer

Fey Wanderers have little conflict with their bonus action aside from Hunter’s Mark. They have few synergies with poison but can work as either melee or ranged poisoners.

Ranger - Gloom Stalker

Gloom Stalkers have little use for their bonus action aside from Hunter’s Mark and gain access to the Archery fighting style. They also frequently strike from stealth, giving them advantage on attacks.

Ranger - Hunter

Although applying the poison might be competing with Hunter’s Mark for your bonus action, the Hunter doesn’t have a lot of uses for their bonus action, making them a good fit. They also gain access to the Archery fighting style to boost their accuracy.

Classes to Avoid for Poisoner Characters

The Poisoner feat uses a bonus action to apply the poison, so you’d want to avoid any class that has a consistent use for their bonus action. This makes Monks a bad fit, even though Kensei make great archers, as they’ll use their bonus action every turn.

Barbarians can make great melee poisoners, but avoid the Battlerager, Berserker, Storm Herald, and Zealot subclasses, as these make frequent use of your bonus action. Also, the wording on the Poisoner feat does not include natural weapons, so Path of the Beast Barbarians won’t work.

Rangers use their bonus action to cast and move Hunter’s Mark. This doesn’t rule out the Poisoner feat, but it does mean you’ll have to choose whether to use Hunter’s Mark or apply the poison. The Beast Master, Drakewarden, Horizon Walker, Monster Slayer, and Swarmkeeper subclasses have frequent uses for their bonus actions, so avoid these subclasses.

Rogues often seek advantage on their attacks to get sneak attack damage, but Cunning Action is a core class feature that uses your bonus action. Additionally, the Inquisitive, Mastermind, Phantom, and Thief subclasses frequently use their bonus action, making it harder to apply the poison. The Soulknife subclass also uses psychic blades which can’t be poisoned. While a Rogue using poisoned weapons is a great concept, it’s harder to work within the confines of the game because of these limitations.

Poisoners Without the Poisoner Feat

If you want to deal poison damage without the Poisoner feat, there are a few options.

The Grung is a race released in a smaller supplemental book, so it doesn't get as much publicity as other races. It has a feature where you can poison a character you touch. This feature makes Monk a great way to apply poison since they're perfectly viable without weapons. The poison is on a relatively low DC saving throw, but when you get as many hits as the Monk does, you're bound to get some poison damage.

Speaking of Monks, the Way of the Ascendant Dragon allows you to change the damage type of your unarmed strikes. One of the things you can change it to is poison. This doesn't do any additional damage, but it does technically make you a poisoner.

Trickery Domain Clerics get a feature at level 8 to add poison damage to their weapon attacks. As noted above, this stacks with damage from the Poisoner feat.

Poison Spray is a cantrip that deals some pretty hefty poison damage (1d12, which scales like a normal cantrip) when an enemy fails a Constitution save against your spell save DC. The cantrip is available to Artificers, Druids, Sorcerers, Warlocks, and Wizards, which means it's also available if you take the Magic Initiate feat for one of those classes.

Other spells that deal poison damage include Infestation, Ray of Sickness, Dragon's Breath, Cloudkill, and Illusory Dragon.

And, of course, Dragonborn characters can choose to be green Dragonborn so their breath attack deals poison damage.

What About Other Poisons?

Dungeons and Dragons has a variety of poisons (22, as of writing this) that are available as items. Although these are not magic items, they can be just as rare. The more powerful poisons are not likely to be available in regular shops. The DM may create a black market that makes these available to players, or they may be treated more like quest items or magic items, handed out by DM fiat for specific reasons.

Having the Poisoner feat and ignoring resistance to poison damage can make you more effective with these other poisons. They also open up some new gameplay mechanics, such as leaving a contact poison on something the target will touch or covertly pouring an ingested poison into food or drink rather than just trying to stab your mark. Some poisons have interesting effects beyond damage, such as incapacitating your foes or forcing them to tell the truth.

If you want to make your own poisons (beyond the basic poison), the Dungeon Master’s Guide has rules on crafting them. Making poisons usually involves harvesting raw materials from dangerous creatures. If you’re interested in crafting or buying poison, talk to your DM about how it works in your game.

Basic Poison is pretty widely available and many DMs will allow you to craft it if you have proficiency with a Poisoner’s Kit, although it’s not terribly effective. The Poisoner Feat is still the way to go for a go-to option to use in combat. If you want to do things besides coat your weapon in poison, look beyond Basic Poison and the more potent poison created with the Poisoner feat.

If you want specifics on what poisons are available in DnD 5e and how to best use them, RPGBot has a write-up on using poisons.

About the Author

Brandon Gregory

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Brandon Gregory is a web developer and writer in the Kansas City area. He's been playing TTRPGs since 2020 and is involved in the disability-related TTRPG podcast Tales from the Crips. He's into classic movies, mental health, and, of course, DnD. Also, he's in a band. One time, they rocked so hard it killed a man.