the best strategy is to build up your ping by jumping around in a heavilly populated area (populated by monsters is fine) and this will slowly bring up your ping if there are enough monsters around
Do this when youre near the person you want to kill, when your ping is about 3000+ try to kill the person, the lag will mean you get in about 3 free hits, they wont know what is going on until the fourth/fifth hit, by which time theyre probably dead.
Another (and slightly easier) way to increase your ping is to use up your own bandwidth using downloads or torrents
For example that time i said i had a ping of 7-8000 was because i was torrenting a discography, i had managed to kill someone i know to be reborn before anyone tried to get me
edit~ this way needs a name
This type of pking shall hence-forth be known as *drum roll*.....
LAG RAPING