I just posted this here since I'm not really showing the hack that much.
Hidden, some source mod if i recall, they remade it in TF2 where 1 player gets to be invisible and hunt others down, kind of like Predator..
I started taunting them, but I tried not to exaggerate cause I didn't want them to leave. At least these 2 were talking, not making strange noises like others. The potential for griefing/trolling is huge.