What I've found on Ramakamil (and on the other Wyr mystics) is they won't attack while they're talking. When they're spouting off their "Delight Enhanced the Lost Souls Dance" or "The Magic Tomes shall Turn to Stones", you can whack away at them.
My problem was that I was so fascinated with the weird things he was saying that I didn't start attacking until it was too late....
This is also true for the Rogues, Rattkins, etc...when they're doing their "thang", you can be attacking them and they won't attack back until they're finished. Bug or design? You decide.
-Sazerac