In WSG @ level 60 I've gotten a few 4000 crit frostbolts with moderate gear and 33-0-18. But what's more perfect about this video is the HK on a Field Marshal, as well as a measly ~200 fire damage hitting him back. Epic on all counts, 5'd!
Basic Spells
* Frostbolt - 3 sec cast, 3500 to 4500 frost damage and 4 sec slow
* Fireball - 2 sec cast, 3910 to 5290 fire damage
* Arcane Missiles - 5 sec channeled, shoots 5 missiles each dealing 1260 to 1540 arcane damage (6300-7700 total)
* Chains of Ice - 10 second root, does not break on damage. Dispellable. (appears to be a chance on hit with frostbolt, similar to mage's frostbite)
* Slow - Reduces movement and melee attack speed by a considerable amount for 10 seconds. Dispella