Poisons in D&D 5e explained
Although save or die poisons haven’t been in D&D since before the 3rd edition, I still regret the time I was running an adventure and a first level character encountered a poison spider. He failed his save and died. Not fun. D&D 5e has really simplified the use of poisons. No more initial and secondary damage. No more ability damage. No onset time. No multiple saves (I was always forgetting to require the second saving throw a few minutes later for secondary damage). And, of course, no save or die.
I am sure there will be more about poison when the Dungeon Master’s Guide comes out, but for now here is my attempt to remove some of the confusion about poisons in the current, fifth edition of Dungeons and Dragons. [As expected, the Dungeon Master’s Guide contains additional information regarding poisons. Starting on page 257 it describes the four different types of poisons (contact, ingested, inhaled and injury). It also has a list of 14 different sample poisons with their descriptions and prices. It also has information on purchasing poison and on crafting and harvesting poison.]
Using Poison
The only poison listed in the Player’s Handbook is basic poison. You can buy a vile for 100gp. You can coat one slashing or piercing weapon or up to three pieces of ammunition with it. Applying the poison takes an action. A creature hit by the poisoned weapon or ammunition must make a DC 10 Constitution saving throw or take 1d4 poison damage. Once applied, the poison retains potency for 1 minute before drying.
The description doesn’t say that the poison wipes off when you hit a creature with it, so you can continue doing damage for 1 minute after it is applied. Plenty of time for the typical encounter. The poison damage is in addition to any other damage the weapon would normally inflict. The creature hit by this poison takes poison damage but doesn’t become poisoned (see below).
Unlike previous editions, the Player’s Handbook doesn’t say that using poison is an evil act. So it is up to the DM to decide. Perhaps some types of poison are more evil than others?
Some poisons do hit point damage, some give you the poisoned condition, and some do both.
Taking poison damage
Poison damage is hit point damage, the type of damage is poison. Most poisons allow a Constitution saving throw to avoid any poison damage [basic poison and poison spray spell for example], but some don’t allow a saving throw [like basilisk poison]. Still others do poison damage on failed save, or half as much damage on a successful save [like the cloudkill spell or dragon breath].
Becoming poisoned
Although a failed saving throw is not always required to receive poison damage, you must always fail your Constitution saving throw to become poisoned. When the description says you “become poisoned” it means that you will have the poisoned condition, which gives you disadvantage on attack rolls and ability checks.
The poison description will indicate how long this condition will last. The weakest last only until the start of your next turn. Others last until end of your next turn, or for 1 minute or for 24 hours. Some last until saved against and allow you to attempt a saving throw each round. The most powerful last until removed by the lesser restoration spell or similar magic.
On a successful saving throw against some creature’s poison, you are immune to this creature’s poison for 24 hours
Additional conditions
While the poison condition is in effect, different poisons may also impose one or more additional conditions (sometimes the additional conditions are only in effect if the saving throw fails by 5 or more). The additional condition might be Paralyzed, Incapacitated or Unconscious. For the Unconscious condition, some poisons allow another creature to use an action to shake the target awake. Although awake, he would still have the poison condition. Another effect could be that you can take either an action or a bonus action on your turn, not both, and you can’t take reactions. Other poisons have you take some amount of poison damage at the start of each turn, or not allow you to regain hit points while you are poisoned.
Diseases
Arguably, the worst poisons are those that leave you infected with a disease.
These allow a saving throw against disease or become poisoned until the disease is cured.
Here are the diseases listed in the Monster Manual:
GAS SPORE – Spores invade an infected creature’s system, killing the creature in a number of hours equal to 1d12 +the creature’s Constitution score, unless the disease is removed. In half that time, the creature becomes poisoned for the rest of the duration. After the creature dies, it sprouts 2d4 tiny gas spores that grow to full size in 7 days.
OTYUGH and DEATH DOG: Every 24 hours that elapse, the target must repeat the saving throw, reducing its hit point maximum by 5 (1d10) on a failure. The disease is cured on a success. The target dies if the disease reduces its hit point maximum to 0. This reduction to the target’s hit point maximum lasts until the disease is cured.
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