You have to complete the "Defeat the Demon King" Battle on the Master Quest map. If you haven't unlocked that map here's how to: Defeating the Demon King tile --> Map Unlocked Adventure Map --> Great Sea Great Sea--> Master Quest Master Quest--> Termina AND Twilight That's as far as I've gotten, but I'm 99.9% sure that's all the maps minus DLC maps and Rewards Map!