Locked Chests

During the first few chapters of the game, you'll encounter locked blue chests in dungeons. These contain some of the best equipment you won't get anywhere else in the game so it is recommended to take note of their locations and loot them later once you have the means to do so. Like ordinary chests, discovered blue chests remain visible on the map, making it easier to track them down individually.

At the start of Chapter 6, you'll be able to pick up the Chest Key in the mid-deck of the Grandship. This is impossible to miss since the chapter will start with the Chest Key right beside you.

*You have to enter the original Grandship. Press the ship icon in your lower screen to get the "Enter Airship" and "Auto Pilot" options. Choosing the former will allow you to access the Engine Room of the Grandship you're using.