Hulen Hairyback is a weaponsmith. If you give Hulen Hairyback the required amount of crafting materials, and pay Hulen Hairyback a fee in gold, Hulen Hairyback will craft you one of the weapons from his "menu". Also, for a fee of 10 gold Hulen Hairyback can customize a weapon for you. This will increase its damage by 20%, but means that only the character and his/her heroes the weapon is customized for can use said weapon.