Thallen has quite a skill set, boasting AoE magic damage, a chance at true damage when he is hit, stuns, additional damage through special strikes and a meaty AoE ranged ultimate that also provides a solid magic resistance reduction. He is also both an Arbiter and Esotericist so has good faction choices, both benefiting from, and helping the majority of both. Thallen works well on his own and great with others, supporting the esotericist mages or making his Arbiter lords skill hit like a truck.