I'm not sure if it's possible to kill the Confessor but you CAN damage her through the bubble. I know Chaos Bolt will will pierce it, and a Ret Paladin with Sanctified Wrath will be able to damage her (25% of normal) as well while wings are up. I have personally dropped her to ~15K left with my Ret Paladin before my wings wore off. You can interrupt or purge the Renew off while she's bubbled, too. I don't know of any other bubble piercing effects -- can anyone else thing of any??
I am not sure what happens if you actually kill her while the bubble is up -- might stop at 1hp or something, or the encounter breaks, or maybe you get free candy or something!
Can someone running a Paladin or Warlock heavy group give it a try on Normal and let us know?

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