I think this has something to do with the interaction between damage over time effects and a crawler's natural health regen, but in my current run I've noticed crawlers that have died to DoTs from my chemical pistol's acid entanglement attempting to attack me from beyond the grave.
I say attempting to attack, since after they try to invoke their sting ability, they simply vanish and cease to exist - leaving no corpse and giving no classic experience. So far, I haven't actually been hit by these phantom crawlers, although I'm uncertain as to whether that's something to do with the bug, or if they're simply missing me. Missing is unlikely since "Crawler's attack misses [playername]" doesn't appear in the combat log, plus I only have 3 agility and 30 points in dodge for escape artist, and I'm playing on DOMINATING, so their melee skill is higher than normal.
I've included a screenshot with the combat log - note that the very same crawler that 'dies' to my acidic entanglement is also the one that attempts to invoke 'Crawler sting' afterwards. He was the last crawler alive in the area, so I'm 100% certain I didn't mistake him for a different one.
My current theory is that this bug occurs when a crawler is killed by an instance of damage over time that is lesser than what it would have naturally have been able to heal back through its base health regeneration - perhaps it thinks that it's still alive since it was able to 'heal' back the damage, then attempts to attack normally, whereupon the game realizes the error and attempts to correct it by just vanishing the crawler out of existence?
