Permanent Potion of Resistance (5e Equipment)
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Potion, Very Rare
When you drink this potion, you gain resistance to one type of damage indefinitely. The DM chooses the type or determines it randomly from the options on the table below. When you drink more than one of this potion, there is a cumulative 10% chance the potion outright fails (If you have used 3, for example, the chance that the 4th fails is 30%, though with its rarity that would be rather ridiculous unless you are explicitly hunting them down.).