1. Player killing between the good and evil races is allowed on MUME.
2. In any way, actively or passively, helping the enemy side is strictly forbidden. See: Rules Interrace
3. Player killing is heavily restricted among the good races. See: Rules Sauron
4. Player killing is restricted for trolls. See: Rules Trolls
5. The use of actions, triggers or automation devices of any kind is forbidden when participating in player killing. See: Rules Actions
6. Special rules apply to Istari when engaging in player killing. See: Rules Istari
7. It is illegal to use "throw-away" characters as spies. See: Rules Spies