In Pokémon Pokopia, the player controls Ditto in human form.
Ditto uses its transformation ability to imitate a human after being left in a world abandoned by people. This unusual premise lets the player experience the game through a Pokémon protagonist rather than a traditional human Trainer.
The human appearance is practical as well as story-related. It allows Ditto to collect materials, craft objects, build homes, restore habitats, and interact with Pokémon across the game world. Ditto can also learn moves from Pokémon it befriends and use those abilities to alter the environment.
Ditto is sometimes confused with Mew because both Pokémon are associated with transformation and unusual biological abilities. In Pokopia, however, the central character is specifically Ditto, whose human disguise drives the story and gameplay.