Believable Hunger and Thirst

Most games prefer to handwave issues like food and water, and many tables don’t even track encumbrance… but maybe your players want to lean into the difficult decisions about what they should bring on an adventure–and what they can bring back. If you want to dial up the detail and grit for survival, I’ll bring you along on the thought process I used when running a Dark Sun campaign in Pathfinder 2e.

Note that–like all content–I’m standing on the shoulders of giants. There’s been a lot of work done by other creators, and I want to send a shout out to Shawn Bowman and all of the work he did with his team to bring out an OGL/ORC compliant guide for folks who want to play Dark Sun in Pathfinder 2e, which you can find here. I also want to send a shoutout to reddit user Thes33 for his post about OSR-style modifications for Pathfinder 2e, which you can find here.

First, I modified the size of rations to more closely align with reality (generously using MREs as a guide). Thus, one day’s ration weighs L Bulk, and 1 day’s meal weighs 1 Bulk.

A medium-sized creature needs 1 ration (or 1 Bulk of normal food) and 1 gallon (1 Bulk) of water per day. (Note that the campaign I’m using this for is Dark sun, so I decided that in order to fit the narrative, I have alternate consumption rates for muls, thri-kreen, and so forth)

Large-sized mounts require 4 Bulk of food and 4 gallons of water per day–or half that if they are sedentary and sheltered from the elements. Huge Creatures need double those amounts. On the bright side, Large creatures double their Bulk limits, and they treat items of 1 Bulk as if they were L (so it takes 10 of them to equal 1 Bulk), so you can throw 10 trail rations in your mount’s saddlebags and it’ll count as 1 Bulk to the mount… but most mounts eat feed, not rations, so you need 4 Bulk of feed. (Of course, the nice thing about kanks in Dark Sun is that they produce globes of kank nectar each day, which you can eat.) Water storage is a bit of a different story, and I built a table representing how difficult it is to carry and pack larger items.

A 1 gallon container of water is L when empty, and 1 Bulk when full.
See table 6-16: Food and Water Storage for details regarding storage and Bulk.
Note that larger containers are unlikely to require mechanical interaction with the rules.

Failing to consume the minimum requirements results in the Fatigued condition after 24 hours:

“You’re tired and can’t summon much energy. You take a -1 status penalty to AC and saving throws. You can’t use exploration activities performed while traveling.”

Dying of thirst

After one day without sufficient water (or two for a Mul), a creature begins to die of thirst, and its drained value increases by 1.

After a second day without sufficient water, the creature increases its drained value again, and it also becomes slowed 1.

After the third day without water, increase its drained value again.

On day 4, the creature’s drained value increases again, and it becomes unconscious. If at any time the creature’s drained value exceeds its maximum dying value (usually 4), it dies.

Dying of hunger

An adventurer requires significantly more calories than the average person. After two days without sufficient food (or four for a Mul), a creature increases their drained condition by 1.

Every additional two days without the full requirement of food, a creature’s drained condition increases by 1.

Other Optional Rulesets

For my Dark Sun campaign, we are also using the following optional rules (with links for the curious):

• Dark Sun Campaign Guide by Shawn Bowman
• Automatic Bonus Progression
• Gradual Ability Boosts
• Free Archetype (limited to psychic, psychic warrior, mind smith, and several custom archetypes inspired from the old 3.5e psionics books by Dreamscarred Press)
• Restricted Spells lists (mostly create food & water, and convenience spells like light)
• Tougher Injury & Dying Mechanics
• Monster Parts Crafting System (from Battlezoo Bestiary)

This is a lot to track, but we’re hopeful that it will give us some of that OG Dark Sun vibe. I’ll post updates as we see how it games out.

If you decide to try any of this (or have already used them), please let us know how it went by joining our Discord server.