Amazons and Necros don't seem to be suited very well to take this one down, because they do best at a distance, which still seems to be the most dangerous place to be against DC. With Teleport, Sorcies should do well (esp. since DC is just highly resistant, not immune, to cold, thus allowing Cold Mastery to help put on the hurt). Paladins probably have the best shot at survival, but the least chance to to much damage (maybe a highly specialized Smiter?). Druids would seem to have good survivability, as reported. Assassins??? Maybe with Lower Resist help and Venom? I think maybe a Barb would have the best chance to put the hurt on DC:
My guess is that, since DC only has 50% magic resistance (compared to 95% to everything else) that Berzerk would be a nice skill to use. If you could tank him yourself, you could use a barb merc with a pumped up +skills to extend his stun time nicely (or switch between Berkerk and Stun, but that might be complicated). Get damage reduction, lightning and fire resist, and Cannot be Frozen (to keep your attack rate up while tanking). His melee damage isn't bad at all. Maybe a little Leap Attack for when he tries to run away or Bone Prison you.
Anyway, just some ideas.
Edit: PS - Gehrke's Sanctuary (Exceptional Unique Tower Shield) has big damage reduction and magic damage reduction, along with OK resists. Normally we want damage reduction as a %, but for a frame-based attack like the pink lightning hose, which is half lightning and half physical, having 11-16 damage reduced per frame could really take some of the sting out of it.
My guess is that, since DC only has 50% magic resistance (compared to 95% to everything else) that Berzerk would be a nice skill to use. If you could tank him yourself, you could use a barb merc with a pumped up +skills to extend his stun time nicely (or switch between Berkerk and Stun, but that might be complicated). Get damage reduction, lightning and fire resist, and Cannot be Frozen (to keep your attack rate up while tanking). His melee damage isn't bad at all. Maybe a little Leap Attack for when he tries to run away or Bone Prison you.
Anyway, just some ideas.
Edit: PS - Gehrke's Sanctuary (Exceptional Unique Tower Shield) has big damage reduction and magic damage reduction, along with OK resists. Normally we want damage reduction as a %, but for a frame-based attack like the pink lightning hose, which is half lightning and half physical, having 11-16 damage reduced per frame could really take some of the sting out of it.