In Bladestorm: Nightmare the player is called to create a mercenary and accept missions that will advance the English or the French cause in the course of the Hundred Year War. The successful completion of these missions depends on a variety of elements that put the player's fighting abilities, strategy, tactical and leadership skills to the test. The Mercenary does not ride to the field alone, but as the commander of an army unit chosen to fit each individual situation as some missions are better fought with foot soldiers, others with lances, archers, light cavalry, or a combination of melee, ranged and mounted units.