Permanent Potion of Health (5e Equipment)
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Because a Permanent Potion of Healing doesn't really sound right. When you drink this potion, it increases your maximum hit points indefinitely (See the table below). In any case, you heal for the amount of maximum hit points added, but the potions can only do so much. Any time you drink one of these potions, the benefits are reduced by the total dice and additional hit points that were provided by previous potions. For example, if you had previously drunk a Permanent Potion of Health, and now have a Permanent Potion of Greater Health, the benefit of the Permanent Potion of Greater Health will be 2D4+2, because the normal amount is lowered by 2D4+2, which is the amount you gained from the lesser potion (4D4+4 minus 2D4+2, not whatever the dice rolled when you drunk the lesser potion, but the dice amount themselves. This prevents negative permanent bonuses, which should never occur from this series of potions). This means that your maximum hit points cannot be increased higher than 10D4+20 by ANY amount of these potions.
Drinking multiple Permanent Potions of Health, even of different kinds, does not trigger a roll on the Potion Miscibility table.