The story takes place aboard the Vessel, a spaceship that originally set out to guide humans, known as travelers, to a new planet. After the travelers died, the ship became inhabited and run entirely by robots. The travelers whose minds were preserved through a process called embedding are growing weak as the Heart, the presence that gives life to the ship's robotic inhabitants, decays and causes the machines to falter. Playing as the robot Mio, the player explores the Vessel in an effort to restore the Heart and carry out the ship's original mission.
MIO: Memories in Orbit is a 2.5D side-scrolling metroidvania platformer. Players control a robot named Mio who explores a vast spaceship called the Vessel, gaining new abilities such as wall climbing, dodging, grappling, and gliding while fighting machines that have gone rogue. Combat emphasizes aerial fighting, and players can equip modifiers that adjust their abilities at the cost of modifier slots. Currency called Nacre is used to purchase upgrades and is lost on death, and fast-travel devices serve as save points across the ship.
