I know they have resistance to Fire.
Cold Damage seems to do a little more than the listed damage against them. But I'm not sure if its because I'm a higher level than them, or some other arbitrary reason like that, rather than Elemental weaknesses.
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Niva Reikan: Warrior/Monk, Kurzick Champion
Arcturus Highwind: Paragon/Ranger
Pet: ROUS
Walker Tam: Warrior, Defender of Ascalon in Training
Nikolia Vasburg: Ritualist/Necromancer
