right, most nasty environments should have some sort of deletorious effect. I know there is already the hunger/thirst rate in place, as well as areas where it is harder to get around, but this would add a bit more realism, to my thinking. Technically, there could also be some pretty nasty effects from being underground for extended periods of time as well, or for being at certain depths. Ands now that I'm thinking about it, ranks in certain skills should lessen the effects of these things, due to your experience dealing with them, as well as specific feats to show advanced knowledge of specific environments.