Koss is a warrior hero who travels with the player during the events of the Nightfall campaign. The player first meets Koss during the opening mission where he assists Kormir in training the player, as well as several other Sunspear recruits. Koss is Kournan and one of several Sunspear heroes that the player encounters throughout the campaign. He is described as having a youthful, almost arrogant belief in his abilities and is very devoted to the Sunspears. He uses his charm, imposing physical structure and loose morals to form a vast intelligence network. This makes Koss a unique and valuable asset to the Synspears as he is one of only a few Sunspears who have morals grey enough to associate with certain less-than-reputable individuals.