Dear Ethical Gamer,
What is the appropriate amount of time to wait before taking out a friendly NPC who is walking right in your path and won't get out of the way?
Patient but Angry
The occasional pawn who meanders back in forth in the same two squares is a frustration well known to all gamers. Your query is a valid one, and there is no easy answer.
Before I go into specifics, I must first clarify that if this NPC has given you any quest-progressing help, information or items, then termination is absolutely unacceptable no matter how long you are delayed. However, for a normal filler citizen, here are the criteria:
I generally start by verbally explaining to the civilian what is at stake. It may seem a futile gesture, but it is this type of simple action that separates the ethical gamers from the cold-hearted profiteers.
You may want to say something like this:
"Sir, for the past several minutes you have been blocking the doorway I need to use. I certainly have no desire to harm you, but you are preventing me from making further progress in thwarting the evil that has overcome this land. I must insist that you move within five minutes or I will have no choice but to consider other action."
Now that the problem citizen has been warned, leave your game for a few minutes and do something you have been postponing - such as getting another beer or apologizing to your girlfriend for ignoring whatever it was she was just talking about. By physically removing yourself from the game, you will usually find you give the NPC more time that you originally allowed, thus increasing the ethical justification for violence.
However, it is a sad fact of virtual life that these measures are sometimes inadequate to compel the stubborn AI, and you are left with no alternative but to assume the role of executioner. If this becomes the case, the deed should be done in a professional and painless manner. This is not the time to use your dagger in order to conserve ammunition.
One shot from a handgun or bow is usually best, preferably when the citizen is not looking. Say some encouraging words first so the character won't suspect his life is in danger such as, "Wow, what lovely weather we are having. Check out that awesome rainbow over there!"
Finally, when the time has come, I typically opt to close my eyes before pressing the button of death so as not to experience any visceral enjoyment from the unavoidable termination of this flawed bit of code.
But once you finally find yourself standing over the slowly vanishing corpse of a former friend, it is important to remember that this was an inevitable tragedy in furtherance of the greater good, then forgive yourself and move on through that doorway before some other jackass comes along.