I would have to say an iceorb sorc with chilling armor and t/s. They just teleport all over the place, and it's extremely easy to dodge missles.
After sorcs, I would have to say javazons. With perfect Ethereal Titans, Stormshield, String/T-Gods, and an 08 vampgaze (or perfect 09), with an inventory filled with faster walk/run charms, will own every char (except sorc) in any legit duels.