He is a fast single entity that deals very little damage, has no mass and doesn't have that good of a leadership. Even in campaign, though in there he and his items are free and most importantly he buffs hobgoblin units to an insane degree. I've taken him a couple of times since he is essentially a wolf raider that is harder to rout, but his use case is very narrow since the enemy needs to have a weak unarmoured caster for him to hit. Even then the simple counter is to just move that character inside an infantry unit since Gorduz can't deal with multimodel units.