My OSR version does CON damage: 2d6 per day without water, 2d6 per minute without air, etc. You get a saving throw to halve that.

My 5e version is here:

http://methodsetmadness.blogspot.com/2015/06/d-5e-fixing-food-and-water.html

You can use HP, yes, but you'll run into the same problem that falling damage has: extremely lethal at low levels, negligible at high levels.

Quote from: Pat on June 24, 2021, 02:58:07 PM

Quote from: Charon's Little Helper on June 24, 2021, 01:39:10 PM
Plus - it generally avoids the issue of the first solid hit winning - since Vitality will likely take the first hit or two.

Even then I still don't like extreme death spirals - but a moderate one can add a bit of depth there without most of the usual negatives of a death spiral.

I'd say that's more a delayed death spiral than a moderate one. Moderate implies the penalties are small, but what you're describing is a buffer before penalties take effect.

I actually meant both - in that there is a buffer AND the penalties aren't too severe.

The Space Western I'm working on does just this. No penalties for being down on Vitality - put at half Life points you're 'bloodied' which gives -2 to all rolls (which is a bigger deal than in D&D - since attacks are 2d10/2d8/3d6 - but hardly insurmountable).

The high HP at high level make sense why those characters would last much longer. Not in realism, but in cinematic / literary fiction world.

AKA, Conan will be the last one standing if his ship runs out of food and water. The rest of the sailors will starve and dehydrate alongside Conan, but they'll die and he'll keep going.

Of course, the amount of damage depends on your edition/campaign.

In OD&D where 1D6 HP per level vs 1D6 is the average weapon damage, then 1D6 damage on Day 4 of no water results in most low level NPCs and PCs dying before Day 8.

And let's not forget that lowering the HPs from environmental damage makes them easier prey for the various wandering monsters.

While its true various rules like exhaustion tracks or damage to attributes works fine, just doing damage to HP is fast and easy. Not realistic, but we're talking about games with HP.

Quote from: Spinachcat on June 25, 2021, 01:41:50 AM
The high HP at high level make sense why those characters would last much longer. Not in realism, but in cinematic / literary fiction world.

AKA, Conan will be the last one standing if his ship runs out of food and water. The rest of the sailors will starve and dehydrate alongside Conan, but they'll die and he'll keep going.

Conan will survive the longest, but not 50 times as a long. Hit points scale too quickly.

Which suggests a solution: Damage for environmental hazards should escalate. Not X per day, but X for day 1, then 2X for day 2, then 4X for day 3, or something like that. Or use the old cumulative falling damage rules: 1d6, then 3d6, 6d6, 10d6, 15d6, and 21d6 at 60' -- or 20d6, since falling damage caps at 20 dice. That's total damage, which makes sense for the sudden stop at the end of a fall. To do it in stages for more gradual forms of dying, it's 1d6 + 2d6 + 3d6 + 4d6 + 5d6 + 6d6.

Extrapolating that into a general rule: Since 1d6 is enough to kill a normal person, decide when people should start dying, and say that's the point at which they suffer 1d6 damage. Then decide the maximum anyone can realistically survive, and set that as the 21d6 threshold. Then spread the rest of the dice in between. That can apply to hunger, drowning, falling, disease, or whatever.

Of course, that also leads to weird results. Ships where all the sailors die from starvation, leaving the entire office corp. Then the junior officers die, leaving the senior officers, and so on. It feels a little too regimented. A save to avoid damage, or at least reduce it to a lower level, might randomize it a bit. Say if you're at the 1d6 stage, a save reduces that to 0. Or if you're at the +3d6 stage, a save reduces that to +2d6. That means at least a good portion of the crew will save and survive, while the junior officers start dying.

Reading the ideas above about how to do environmental damage with hit point, I can say that I've tried most of those and a lot more.  You need some pretty convoluted additions to the game to get hit points to work even sort of reasonably with environmental damage.  I take that as an indicator that hit points is the wrong approach for this in the first place.

Quote from: Mishihari on June 25, 2021, 02:46:16 PM
Reading the ideas above about how to do environmental damage with hit point, I can say that I've tried most of those and a lot more.  You need some pretty convoluted additions to the game to get hit points to work even sort of reasonably with environmental damage.  I take that as an indicator that hit points is the wrong approach for this in the first place.

First edition Dark Sun dehydration causes Con loss. A character loses 1d6 Con if they don't get enough water, or lose 1d4 Con if they get at least half the required amount.
A character reduced to 0 Con is dead.