A friend of mine suddenly had wierd issues today when entering Death Shroud on his Necromancer.
Testing things it turned out to be an issue being caused by using a full set of Superior Rune of Vampirism.
When you enter DS and it flips to your life force, the rune may think you went below 10% health and transforms you into mist which locks you out of your abilities for 3 seconds.
He kept getting lockouts all the time (especially when getting hit while in DS), but when he used only 5 runes from the set (by removing a piece of gear) he had no issues at all anymore and everything functioned normally again.
So it seems that there is a bug when having a full set of Superior Rune of Vampirism on your gear as a Necromancer and turning into DS.
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