The Inventory 
is where the items you receive are stored. It is organized into sections:
Energy, containing items that replenish Energy.
Tools, containing items that help you complete game levels.
Chests, containing item bundles.
Talismans, containing items that speed up game progress by increasing Experience, Coins, the chances of finding an item, etc.
Resources, containing items needed to assemble collections.
Bandits, containing items for arresting bandits and assembling bandit-related collections.
Events, containing all event-related items.
Almost all items in the Inventory can be obtained by playing the game, as well as purchased. Some items can only be activated in the Inventory.