You gain the following benefits.
Ability Score Increase. Increase your Dexterity, Constitution or Intelligence score by 1, to a maximum of 20.
Brew Poison. You gain proficiency with the Poisoner’s Kit, if you don't have this proficiency already.
Potent Poison. When you make a damage roll that deals poison damage, it ignores resistance to poison damage. As a Bonus Action, you can apply one dose of poison to a weapon or up to three pieces of ammunition. Once applied, the poison retains its potency for one minute or until you deal damage with the poisoned item, whichever comes first. On a hit, the target must succeed on a Constitution saving throw against the DC as stated in the item's description, or against a DC equal to 8 plus the modifier of the ability increased by this feat and your Proficiency Bonus — whichever one is highest — or suffer the effects of the poison. These options for save DC's apply to all poisons, including ones that do not do damage or are not applied to weapons or ammunition, such as inhaled poisons