The Forge of War is an accessory for the Eberron setting that explores the history of the Last War. New character options allow players to explore battlefield backgrounds, the magic of war, battle scars, and the benefits of working as a team. Campaign seeds help the Dungeon Master introduce the themes and events of the Last War in a current-day campaign or send characters back to their wartime days through flashbacks or actual time travel. A comprehensive overview of the Last War provides details on the events, armies, battlefields, and themes of Eberron's greatest clash of nations.