Add (thirst) so characters become thirsty and need to drink. Different things could quench your thirst better than other things, such as, water, milk, alcohol. If a player doesn't drink they can die of thirst. Add (hunger) so characters become hungry and need to eat. Each stage of hunger could cause you to lose more and more strength. Strength could drop 3 points per hour or 10 points every 3 hours. This would not affect their hit points but would control your strength ability. In different stages you could receive different warnings. Add (Exhaustion) so characters become tired and need to sleep. After a 12 hour period of game play or more depending on strength a character would need to sleep. They would have to find a bed or make a camp. One minute for every hour they were awake they would need to sleep to fully replenish. A character could be seen sleeping in his bed but could not be harmed while sleeping. Also, logging out could be changed so a character would have the ability to sleep while logged off, this would bring them back refreshed. If a character did not sleep within the 12 hour period, then crafting and skill gain could become impossible, also, the gathering of ores and other resources could become difficult, making the character's abilities worthless without sleep.