The game now has three difficulty levels: easy, normal and hard. (Thanks: PL-BR, Sleppy)
Previously, the game only had a hard level of difficulty.

How easy and normal modes differ from hard mode:

• Damage from enemies is less
  
• Hunger and thirst drop slower
  
• Health from hunger and thirst drop slower
  
• Damage from poison is less
  
• Plague damage is less
  
• Dysentery disappears faster
  
• You need less sleep
  
• Sickness affects less
  
• Dirt accumulates slower
  
• Temperature has less effect on health
  
• Dehydration is weaker
  

Also corrected errors in the text and in the recipe for the iron staff (Thanks: Psichi)