I'm not sure if this has been reported before but I'll try to describe a bug I experienced twice (running the Mac client):
As I understand it, when you attack the netch while it's floating in the air it does some kind of powerful counter attack. Twice while fighting this boss I attacked it while it was floating and it appeared to do some kind of attack on me but it caused me to enter a kind of zombie state where my health was about halfway and didn't change (I was invulnerable), I could still run around (and my teammates observed me doing it and said I looked like I was floating), but I couldn't do anything besides move. The "You can't do that while dead" message appeared when I tried to do normal attacks and I couldn't use any abilities, and the attack jerkily played the animation repeatedly.
This effect continued after the rest of the team wiped (they were missing a damage dealer and had no way to resurrect me) but if i logged out I would find my character dead after logging back in. We managed to beat the boss (the workaround being to not attack the netch if it wasn't on the ground)
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