Key Items are unique, story-critical objects that often unlock new areas, progress the plot, or grant special abilities. These cannot be sold or discarded. Examples include the Sorcerer's Ring (used for puzzles and activating switches), the Albiore (your airship), and various plot-specific documents or artifacts. You'll acquire most key items automatically through story progression. Collectibles, on the other hand, are optional items that often contribute to side quests or unlock special rewards. The most prominent collectibles are Capacity Cores, which are vital for character growth (see 'Characters & Builds'). Other collectibles include Recipes for cooking, which expand your culinary options and provide more diverse buffs. You'll also find various materials that can be used in the Synthesis system. Keep an eye out for Collector's Books, which track your progress in finding all items, and Monster Books, which record information about defeated enemies. Completing these books can sometimes unlock special titles or rewards. Thorough exploration and interaction with NPCs are key to finding all key items and collectibles.
