BUG/Multiplayer/Official 3915 PVE
Was fighting two thralls in the volcano yesterday and one just turned invisible mid fight. I could hit it but it would not die. It followed me across half the volcano. Was seriously creepy hearing the footsteps and the swooshing of its misses until it hit me again. I hit the thing at least 20 times (I know this because the blood was visible). Finally I stopped hearing it when I got near my base. Not sure what caused that and I have never had it happen before. They were the thralls that sit down (almost always fighters) near the cooks and alchemists.
Steps on how to reproduce issue: