Invincible Enemies! (prt 2, return of the bug) Pun Intended

A while ago I posted about enemies that randomly stop taking damage for no reason. It's usually amidst chaos and fighting, where one enemy that shows NO features of invulnerability suddenly just stops taking damage. Not slowly damaged, not healing, the monster just stops taking damage of any kind. Sometimes the monsters bug out and do nothing, other times they mill about, other times they continue fighting.

This time, I am in the mines and this bug creature stops moving and stops taking any damage. As you can see, it's the type to have a small health pool and it's not a rare. It has no reason to be immune to damage within my Righteous Fire circle, but it totally is.

Again, I want to reiterate, this is not the first time I've encountered this bug nor it is the first time I've reported it. This is the first time I have been able to get a clear screenshot, though.

The bug report number is 2,625,489,324