Unlike most games, Dear Esther has no inventory system whatsoever. You cannot pick up, store, or use any objects. This means there are no puzzles that require item manipulation, no resources to manage, and no gear to equip. The game wants you to focus solely on the act of walking and listening, without the distraction of managing an inventory. This design choice contributes significantly to the game's minimalist aesthetic and its emphasis on the internal journey rather than external challenges. You are simply a pair of eyes and ears moving through a world.
