I was able to dire charm one of these today. Very nice pets. Self buffs with Arch Shielding, O'Keils Embers, Diamondskin, O'Keils Flickering Flame. I was able to stick a conviction on him, so he had lots of mana. His nukes take the mobs in zone down a bubble of health at a time, and he constantly nukes. I think this means though that their level is not always that high. If I recall, you can only dire charm 45 and lower. Unarmed he would hit for 92 and 41 frequently. He would miss aobut half the time. He seems to have a tone of hit points, as his life dropped very slowly when he fought, and most of the mobs in the zone missed him most of the time. He often roots his opponents, but isn't smart enough to stay at a distance.
I haven't encountered the IC yet, personally I dont want to. These things can spawn as the PH or guards of the Ghoul Lord, so keep a look out and attack them the moment they spawn, or they get some nutty ideas. For example, while we were busy with a Bok Knight, the Guk spawned right behind me. Last thing I heard before having the heads of my entire party slam into the ceiling was the Wiz casting Gravity Flux. Very fun to get hit with. =)
I learned about wizzies at an early age hunting in derv groups. If you let one cast twice somebody was dead. If one popped on you in the middle of another battle, chances were good that several somebodies were dead. I always fear NPC wizards.....
These guys are bad, if you don't get on them soon as they spawn they WILL cast ice comet, watching one of your group mates just die instantly is unfun.