Project Vex is a game that makes use of Permanent Death. Additionally, Player versus Player combat is unrestricted.
There is a problem here, which, if not fixed would likely cause Project Vex to wither, never reaching its full potential.
The first step, is to divide players into two groups -- those who wish to engage in combat, and those who do not.
The mechanic for this shall be fairly easy: If your weapon is drawn (or you are unarmed, but in a combat ready stance), you are fair game for anyone. If you have had your weapon drawn or been in a combat ready stance recently (as of yet undetermined length of time possibly around 15 seconds) you are still fair game. If not, you are considered a non-combatant, or no threat.
Attacking a player who poses no threat is still possible, however... a character must be penalized in some way that does not interfere with other game mechanics if they kill the other player who posed no threat.
I have considered branding the character as a murderer (permanently), however, an assassin type should be able to kill their target and still somehow manage to get away with it, without being permanently branded as a murderer, along with various other scenarios.
Now mind you, you can defeat a player without killing them, and the majority of the time, that is how battles will play out. Thus, a murder is only committed when the other player dies, not when they are defeated.
There is also cause for concern in relation to a character purposefully keeping their weapons sheathed and instigating a battle, drawing their weapon only after the fight has begun to brand the other character as a murderer, should they lose. This can easily be fixed by determining a murder to be the death of a character that began the fight unarmed, not in a combat stance, and ended unarmed, not in a combat stance for the last few seconds (~15 seconds?).
Assuming the above mechanic works well enough, we are back to the concern of consequences for murder that do not interfere with other game mechanics.
Perhaps the use of a disguise, given enough ability in the "skill" could allow a player to temporarily hide their "murderer" status?
The Full PvP aspect of the game, and the Permanent Death are not likely to change, so I would like to focus any commentary/discussion regarding this on how to best handle the madness that results from completely free PvP, thanks.
A few things I feel I should add:
You can never be branded as a Murderer in your own community for killing a character outside of the territory of your character's community (kingdom, lair, self, etc.).
There are no levels in Project Vex, and generally speaking, no character is ever impossible to defeat by any other.
Items and wealth are fairly easy to acquire in Project Vex.
Ah, and also: NPCs will react to a character branded as a murderer if their fame / infamy is high enough.
Regarding that, a character's fame / infamy is a hidden score based upon their quantity of (ir)reputable acts. Players will be unaware of a character's brand as a murderer if the character's fame / infamy is low enough. A character with a high "skill" in something akin to local knowledge will have a higher chance of being aware of a murderer status.
Characters must still deal with a high disguise-type "skill" to recognize a character at all.
Another note: The effect of killing another character branded as a murderer is still undecided. It may be based upon the community; some seeing murder of a murderer as just, while others only allowing "authorities" to properly deal with murderers.
All in all, it seems that how a murderer is dealt with is entirely subjective. Perhaps I need to come up with an entirely different system for limiting PvP? I am as of yet, unsure.