Own Worst Enemy (5e Equipment)
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Own Worst Enemy
Price per dose: 30gp
A regular poison mixed with a liquid that imitates a health potion in every way except the healing properties.
A creature can make a DC 15 Wisdom (Perception) check to tell it isn't a health potion and a DC 20 Wisdom (Perception) check to tell that it is poison. When this poison is consumed, the creature must succeed on a DC 15 Constitution saving throw or take 4d8+10 poison damage.