Water 
Water is vital in Khemri. Remeber lads when you travel be sure to carry enough of it. You don't want to be caught between oasis without water. That spells death for sure. Those undead, the only thing they have going for them, is that they don't need water. Lucky buggers. 

In the desert, water becomes a crucial resource, viewed as being as valuable as the wealth in the tombs (especially to those who have had none for a few days!) Water is represented by a water counter that each warband will have, and must keep track of, (very much like experience). Each warband has a S rating, (basically just add up their S, the total is the rating). This would represent the total amount of water that the warband could carry. Creatures/models that cannot have equipment also could not carry water (dogs, Possessed, etc.) Any extra animals (horses, for example) would be able to carry water equal to their strength as well. Once this rating has originally been determined, it should be pretty easy to keep track of it when new characters are added, characters die, advances are rolled, etc.
The warband will start with a full ratio of water units. They would expend it after each battle in the following way:
-1 Water Units for every model (-2 for large)
-1 Water for Animals (Horses, Dogs, Jackals, etc.)
-1 Water Units for every model OOA
Note: This could be modified if the warband was able to consume less, (due to being accustomed to the conditions, being especially hardy, etc.) Obviously Undead models require no water, but living members of Undead warbands will. Any Undead (or other model) that does not require water, but can carry equipment may carry water.
Note: A warband may choose to not give certain members within its ranks water (so, to preserve water for more important warband members by denying it to less important ones.) This rule must be used within reason (you wouldn't deny your Heroes water, for example, but a slave could be turned away.) Also, when a warband did not have enough water to go around, it would be up to the leader to determine who got the remaining water rations.
Note: If a model dies or loses his equipment, the water he was carrying is also lost.
Getting Water: The water warbands can receive is determined by where they are resupplying: see Equipping/Trading Rules (in the Bazaar).
Weather: If it rains at all during a scenario, then all warbands involved get their water ratio filled to its maximum, and do not expend water after this scenario. If the weather is "Hot", then D3 units of water have evaporated due to the temperature. If the weather is "Hot as Hell", then D6 units of water have evaporated. (See weather rules).
WITHOUT water: A warband without water would begin to suffer ill effects. On a game each member who had no water would roll against his T (on a D6). A passed test would mean he was able to resist the effects of the lack of water. A failed test means he would succumb to the lack of water in some way. Roll a D6 to determine the effect:
1 - Mirage: Model would have to take a Ld test any time he moved. A failed test would mean he would walk distance intended in a random direction.
2 - Exhaustion: After the first round in combat, the model would suffer a -1 to S.
3 - Parched Mouth: Can no longer extend Ld to models. This affects any model with the Lead ability.
4 - Dizzy: +1 to any injuries incurred on the Injury roll.
5 - Weak: -1 to T for game.
6 - Dehydration: Model cannot fight this battle.
Each round afterwards that the model does not have water, the test must be made again, but with a cumulative -1 to T. When the model's T reaches 0 on this test, he has succumbed to the lack of water and dies.