Koss

Koss is one of the the Heroes (customizable party NPCs) available in Guild Wars Nightfall.

He is a member of the Order of the Sunspears.

From the Nightfall product info page:


 * KOSS: A cheerful, boisterous fellow Sunspear, Koss has almost as much faith in you as he does in himself.

Recruitment
Koss joins the party after completing the Into Chahbek Village quest.