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• PlayStation®: NA and EU megaservers for maintenance – December 15, 4:00AM EST (9:00 UTC) - 12:00PM EST (17:00 UTC)
Arcanist Shields and random NPCs targeting

As you can see, shields target an NPC, that even is not damageable by the boss, causing charges get wasted.
Either remove NPC (and minion) from targetlist entirely or increase the target count.
I mean why i want to shield a sorceress clanbann, if there is sorceress, that is going to die because the clanbann eats the shield.