The inventory is the menu that pops up when the player presses the "E" key. In this screen, the player can equip armor, craft items in the 2x2 grid, and place items in the Hotkey slots. There are 4 armor slots in the inventory (Helmet, Chest, Leggings, Boots) Armor must be directly placed in these slots to be used. If it is just held in the inventory, it isn't used. In the inventory screen, the players custom skin can be seen, wearing whatever armor is equipped (If any). Items may be stacked in the inventory screen.
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