Ghost Giant is a virtual reality puzzle game where the player helps a young anthropomorphic cat named Louis with his life and work around a small French village called Sancourt. Playing as the ghostly giant, the player can reach out and manipulate the world unnoticed, able to poke, grab, and blow into the microphone to interact with the environment. These actions allow you to to tear away walls, move objects about, and utilize tools like a magnet or paintbrush to solve puzzles.
When in one of the twelve levels, the player can poke Louis for hints on how to proceed and there are small collectibles like hats, caterpillars, and pinwheels to find. Certain situations will require the player to spin buildings, lean around corners, or trick townsfolk to progress the story to find out why Louis tries to avoid talking about his mother while repairing the friendships that are on shaky ground due to his lies.