As some of you may have noticed there is a quite a significant issue on the Washington (might be on PEI too) Sandbox server, which is the more or less notorious "invisible guy".
To be brief, someone seems to have found a way to not only use the /vanish and /god commands, but also to make it impossible for players to find out anything about their identity, as he/she/apache does not appear in the players list nor in the kill-screen (notably they do appear as ?[?], though I don't see how that can be of any use).
Here's a screenshot I got of the kill-screen: http://imgur.com/a/28orw
I think it goes without saying that someone with this kind of power who also abuses it pretty much makes the game unplayable, as I have lost more than 0.04 points of kdr just because of it.
For the sake of the server, not mine, please take action.