Was tanking Cazic Thule for roughly 12 minutes. At 20% or so, I popped my ST disc (ring of the clawed guardian). I had 8600 or so AC. A few seconds later, he hits me for 5333, 17996, 16536.
Um..He hits my medding wizard with 1.6k ac for 11900.
I don't have logs, but figured I'd post..a frustrating end to what would have been our first CT kill :/