I don't know if you have access to any of the Dark Sun campaign materials, but there was a lot of stuff written about what happens to characters in the wastes.
First off, in high temperatures, armor becomes a real burden and characters wearing armor fatigue (aka take ability damage, etc) much more quickly than unarmored characters, not only because of the extra weight but because the material traps heat and dehydrates the wearer faster. Such characters have two choices: 1) continue to wear the armor at increased risk which might end up making them useless when they are attacked anyway, or 2) ditch the armor and be more vulnerable to nasties that want to make a meal out of you.
Then you've got heat stroke, sun burn, dehydration, sink holes, bad footing, sand storms with no shelter to seek, wind burn. There's a real danger of getting lost as you have no kinds of consistent landmarks (except the sun or stars) by which to judge your location, and the winds will keep you from locating your own tracks to retrace you steps. Not to mention, you can't keep things clean as sand gets everywhere and is nearly impossible to be rid of.
One thing that most people forget about is that open desert isn't just hot. At night, after the heat dissipates, the desert can get extremely cold as well. Characters who don't have proper bedding to keep them warm will probably get poor quality sleep (and thus may recover fewer hit points or perhaps none at all).
There's also the issue of eating. Except for what materials you bring with you, you generally have no wood to burn to build fires or torches which means that any food you acquire will have to be consumed raw (uncooked Thri-kreen meat...yuck). This can cause a host of its own problems (digestive and otherwise). You can't boil water to purify it and you can't cauterize wounds to prevent infection.
Just some basic thoughts to keep in mind. I think the 3.X DMG goes into temperature extremes and dehydration, but most of the rest requires a little more research to get mechanics. Slow ability damage is a good one though, especially Dex and Con as those are really important to any character, regardless of class.
Last edited by Webhead; 08-08-2008 at 10:50 AM.
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