Zapa
I have encountered a bug 3 times now where my health remains negative after reviving from death. Once when I clicked return home, it did not return me home and left me in the screen I had started the fight. It did not fix the issue by relogging. I was unable to attack anything nor cast any spells, my other group members were unable to summon me. I had to manually walk home to fix the bug.
It has also happened to me twice when selecting staying to fight option. It did the same things where my health remained negative and was unable to cast or be affected by spells and unable to attack mobs. It was fixed by walking off the screen and back on in this instance.