When you find this kind of thing occurring, please call on the assistance of the CS team. If this is found, you can be sure that the fellow shall be appropriately staked out and left to dry. Warping and other such exploits aren't fair for those that choose to play as the game's designed, and the CS team jump to end such issues as they're alerted.
Help us to catch 'em by letting us know when you see it!
~Gnobrin!
LINK
(Gnobrin) Re:Ghosters
