Toxic Warden

You gain proficiency in the poisoners kit and alchemical kit, and you are able to craft different poisons for different uses. You are able to manipulate these toxins to best fit your fighting style.

Toxic Tools

Starting at 3rd level when you pick this subclass you gain proficiency with the alchemical kit and poisoner’s kit.

You can spend an hour of work conducting a poison when you have the proper materials for the poison (either having the materials or buying them outright) and when you do so, you create a number of those poisons equal to your proficiency bonus rather than just one, as a normal person would. However, you still need to make an Intelligence (poisoners kit) check to create poisons. The DCs for poison are as follows.

Item                                                   Price Per Dose                                   DC

Assassin's blood                             150 gp                                                  5

Burnt Othur Fumes                         500 gp                                                  17

Carrion Crawler Mucus                  200 gp                                                  7

Drow Poison                                    200 gp                                                  7

Essense of Ether                             300 gp                                                 10

Malice                                               250 gp                                                 8

Midnight Tears                                1500 gp                                               30

Oil of Taggit                                     400 gp                                                 13

Pale Tincture                                   250 gp                                                  8

Purple worm poison                      2,000 gp                                                30

Serpent venom                                 200 gp                                                  7

Torpor                                                 600 gp                                                20

Truth Serum                                         150 gp                                               5

Wyvern Poison                                   1,200 gp                                              30

Toxic Lifestyle

Your time working with poisons have given you knowledge on how to make the most of what you have. You can apply a poison to your weapon as a bonus action. Once you have applied poison to a weapon it retains its potency for 1 minute, or for a number of attacks equal to your proficiency bonus.

Whenever you deal poison damage to a creature that is your favored foe (from Tasha’s cauldron of everything) you deal additional poison damage equal to your level. At 17 level this bonus is doubled as any weapon you wield begins to become infused with your poisonous biology.

Toxic Tolerance

At 7th level you gain proficiency in Constitution saving throws when resisting poison, acid, or necrotic damage of some kind, or the poisoned condition.

You gain resistance to your choice of acid OR necrotic damage. you also gain resistance to poison damage outright.

Additionally, you can add your proficiency bonus to poison save DC’s by adding in some secret brewing ingredient that is determined by your dm.

Resistance

You can choose between acid or necrotic damage. 

Resistance

Choose either acid or necrotic.

Deadly Corruption

At 11th level you know how to spread the blood of a poisoned creature to another. Whenever you damage a creature that is currently under the effect of one of your poisons, you can use a bonus action to cut them in such a way that there blood spreads to another target within 15 feet of the original, forcing them to suffer the effects of the poison that the original target was suffering from, or make a con save to resist it.

If a creature is immune to poison damage when you attack it with poison, it is instead resistant, and resistant creatures are treated as not having resistance. Creatures without resistance or immunity make the save with disadvantage.

In addition, you have advantage on intelligence (poisoner’s kit) checks to make new poisons.

Toxic Blood

At 15th level, your times with poison has changed your biology, and your wounds and injuries give off noxious fumes and toxic blood. You are immune to poison damage.

Additionally, when a creature hits you with a melee attack, you can use your reaction to expose them to your toxic innerworkings. The target must succeed on a CON save equal to your Ranger spell save DC or become poisoned until the end of its turn, and if the target is immune to poison you can instead spray your acidic blood over the targets armor or weapon, giving them a -1 to AC or -1 to the damage their weapon wields if these penalties go to -5 the weapon or armor is destroyed.