Starvation
Starvation and thirst isn't totally clear how it's handled everywhere, so this is a summary of that. This article is written for PF2, may be expanded or may be used for other sstems.
Core Rules
Core Pathfinder 2
Typically characters eat and drink enough to survive comfortably. When they can't, they're fatigued until they do. Without water, after a number of days equal to a creature's Constitution modifier + 1, the creature takes 1d4 damage each hour that can't be healed until it quenches its thirst. After the same amount of time without food, it takes 1 damage each day that can't be healed until it eats.
Core Pathfinder 1
Characters might find themselves without food or water and with no means to obtain them. In normal climates, Medium characters need at least a gallon of fluids and about a pound of decent food per day to avoid starvation. (Small characters need half as much.) In very hot climates, characters need two or three times as much water to avoid dehydration.
A character can go without water for 1 day plus a number of hours equal to his Constitution score. After this time, the character must make a Constitution check each hour (DC 10, +1 for each previous check) or take 1d6 points of nonlethal damage. Characters that take an amount of nonlethal damage equal to their total hit points begin to take lethal damage instead.
A character can go without food for 3 days, in growing discomfort. After this time, the character must make a Constitution check each day (DC 10, +1 for each previous check) or take 1d6 points of nonlethal damage. Characters that take an amount of nonlethal damage equal to their total hit points begin to take lethal damage instead.
Characters who have taken nonlethal damage from lack of food or water are fatigued. Nonlethal damage from thirst or starvation cannot be recovered until the character gets food or water, as needed—not even magic that restores hit points heals this damage.
Core DnD 5e
Food: Small or medium creatures require 1 ration of food per day. They can go without food for a number of days equal to 3 + their Constitution modifier (minimum 1) before suffering 1 exhaustion level per day thereafter. A normal day of eating resets the count of days without food to zero.
A creature on half rations counts as going a ½ day without food (and these half days accumulate until they can eat full rations).
Water: Small or medium creatures require 1 gallon of water per day, or twice that in hot weather. A creature on a half ration of water must succeed on a DC 15 Constitution check at the end of each day or suffer a level of exhaustion. If they drink less water than that, they suffer a level of exhaustion automatically. If the character already has one or more levels of exhaustion, the character takes two levels in either case.
Waterskins hold a half-ration of water.
Recovery: Any exhaustion suffered from lack of food or water cannot be removed until after a full day of normal consumption.
Large & Tiny Creatures: Tiny creatures require one-quarter ration of food and water per day. Large creatures (like horses) require four rations of food and water per day.
Homebrew
Drink
- 1 gallon per day (2 waterskins) or twice that in hot weather or even more in hotter
- Half ration: Fortitude DC15 + days or take a Fatigue level
- Less than half: After 1 day + Con mod Watches (min -1), take D4 thirst damage
1 day + is ok
- Then: D4 thirst damage per Watch until the same time has passed again
Food
- 3 days + Con mod days (min -1)
References