As you approach the end of an Age, you will face a 'Crisis' that forces you to adopt negative policies to balance the world stage. Use this time to secure 'Legacy Points' by completing era-specific milestones. These points are vital, as they determine which powerful Civilizations you can evolve into for the next Age. For example, owning three Horse resources in the Antiquity Age as Rome can unlock the option to transition into Mongolia during the Exploration Age.