The Lord of the Rings
The Rohirrim arrive. The armies of Gondor and Rohan fight the armies of Mordor in the Battle of the Pelennor Fields. There, King Théoden is killed. Dernhelm, who was really Éowyn (a woman), kills the Witch-king with Merry's help. Aragorn comes with a fleet of black ships and another army of men from southern Gondor up the river Anduin. Together they win the Battle of the Pelennor Fields.