Boon of Poison Mastery

Epic Boon Feat (Prerequisite: Level 19+)

You gain the following benefits.

Ability Score Increase. Increase one ability score of your choice by 1, to a maximum of 30.

Antitoxic. You have Immunity to Poison damage and the Poisoned condition.

Perfect Poisoner. Once per turn, when you roll dice to determine Poison damage a creature takes from your attack, spell, or feature, you can instead use the highest number possible for each die.