If you look at the various ways that PKing is done in other massive multiplayer aspects each have their advantages and disadvantages.

Take Everquest with its racial or diety wars,  usually one side ends up lopsided over another but, you cant kill your own guys ( frag ).  

DAOC - proper   you entered a fronteir area where pvp was open in certial regions,  only to opposing teams.  but ou could do it based on individual or team efforts.

DAOC - pvp   you could kill anyone anytime -  this type of open pvp usually spawns hordes of the most powerful classes beating up on everyone else and entire guilds made up of only a few classes or (builds) dominating the rest of the server until the game makers are forced to nurf the class or make balance changes.

Then you have Shadowbane which was full pvp also,  and ran into the same problems a daoc pvp

I think that PVP is almost a neccesary part of any roleplaying game as it allows for justice amung players, but i also think there should be penalties involved in the pking.   Some games try to do this with factions,  others with a \"karma\" that makes those players evil.   I think taking some of all of these might be the way to go for a productive pvp system



Holding players accountable for their actions is the toughest thing that any game can accomplish,  and doing it in a manner that will attract players is even tougher.   lets do some for instances...  the first thing a pker will ask is,  whats the loot rules.

No loot?   well a pker that can kill without worry of losing his items if he himself is killed,  attracts tons of griefers but the antipkers like it because they dont have to worry about losing hard to get items.

Partial loot - this is always tough,  because the only way ive ever seen this effectively work was in bad game that had good intentions.   A pker who killed and killed gained negative karma and once deemed evil there was a % chance that that person would drop an worn or weilded item based on teh percentage of negative karma.

Full loot,  pkers love it rpers hate it.  but it does hold pkers more accountable if they get caught,  and what you normally end up with is nekkid pkers running around trying to get a blind kill on an unsuspected victim.


So how do you allow pk without running into major problems?    I think the idea of making PK regions  that only characters over a certian level can enter is the best beginning.  as far as rewards and penalties,  i like the idea of being able to kill whomever you want,  but if you kill players way under your level you should be penalized for it.  

I dunno  i dont have an answer i am just offering up what other games have done and not done ... to stir some conversation