This is how to kill friendly targets in a ArcEmu based server.
*Tested and Confirmed on the lastest Rev*
Requirements:
Lag, Or a Lag Switch.
Make sure there is something attackable in the distance which you can click on.
What you need to do.
Target the hostile target and right click so it starts to auto attack but it tells you that your out of range, Activate your lagswitch or wait for a lagspike or unplug your Ethernet cable for a second and Quickly right click your friendly target and voila, you will start to hit him with white auto attack hits only.