I'd call this a minor non-issue bug; just jotting it here in case it has yet to be mentioned... Upon late game rounds whilst farming, call it level 70 - 90, one or two monsters become impenetrable and take no damage. It doesn't seem picky on which monster this happens to; as far as I can tell, it occurs during circle work, whether it be the map objectives or music box. The monster can still harm you, and they seem to move faster than usual. Dashing your way across the map to force a respawn rectifies the issue.
#🔐 Invincible enemy
shadow remnant
queen siren
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