Howdy, we are doing a public playtest of our incoming Halloween update a bit later today. Wanna know more? Halloween themed maps and a new game mode called "Ghost Town" which features, yep, ghosts. And those weird green shaded weapons, now you can call them "ghostly weapons".
http://steamcommunity.com/sharedfiles/filedetails/?id=332765970
http://steamcommunity.com/sharedfiles/filedetails/?id=332762815
Opt-in the beta branch to join the fun! Playtest starts in 20 minutes since this announcement goes live.