So, I just encountered him too. Completely invincible, unless (it seems, or so I've read) you 'glitch', which we should not have to do.

He's an absolute unit of double-thick brick wall.

i believe he was nerfed already, same as this boss with shield protection, and now is much easier to kill them

it is not nerfed at all, this boss spawn some adds that heals like crazy.every hit i make the adds heals him twice the number, i fought him for 30 minute with me spamming every skill on bar but his health didn't even dip below 90% other boss i can kill in less than 5 minute

he somehow always spawn for me on 3rd expedition. it is extremely frustrating, please nerf any and all kind of healing from high end expedition boss ,,,,

i was on expedition 179,

strange cause i have no problem with killing him after patch 1.0.8

Anyone saying the Pacified Aurora Knight doesn't need fixing is either;
1. a Clueless Dev
2. a fanboy
3. not playing at a level where they become impossible
4. is playing offline with a zillion DPs build
5. hasn't played since BE was nerfed into the ground.

i think you just have something wrong with the build, cause im killing him in muliplayer on 189 when the rest of the party is dead