Siege engines are not used in combat at sea. Item bonuses Nobles may possess items which grant attack, defense or missile bonuses in combat. Only one item may be wielded for each category. If the noble possesses multiple items with bonuses in the same area, the item with the largest bonus will be chosen. He would not use the Sword of Death.
Nobles automatically use items with combat bonuses in battle.
No special orders are needed to wield them.