Sometimes when you use Clouding Swarm (vampire Bat Swarm ultimate's morph with invisibility) on a group of Monsters or NPCs, one or more will reset due to your invisibility. By reset I mean run back to position and restore to full health.
That happens while you're still hitting them and it's not a distance issue from their starting position. I've tested it and sometimes their starting position is 1-2 meters away, so while you're attacking them they just turn away from you and are back to full health while they are still being hit.
I've /bug 'ed it in game. I've only seen one more person mention it on the thread with known 1.2.3 issues, but it's not added on the list. So this thread is to raise awareness and if you've suffered from this before, know that you're not alone.
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