Super Mario Odyssey is a platform game in which players control Mario as he travels across many different worlds, known as "Kingdoms" within the game, on the hat-shaped ship Odyssey, to rescue Princess Peach from Bowser, who plans to forcibly marry her. The Kingdoms in the game return to the exploration-based level design featured in Super Mario 64. Each Kingdom has Mario searching for and clearing various objectives in order to obtain items known as Power Moons, which are the power sources of the Odyssey and grant access to new Kingdoms. Checkpoint flags littered throughout each Kingdom allow Mario to instantly warp to them once activated. Certain levels feature areas called "flat" zones, where Mario is placed in a 2D side-scrolling environment similar to his appearance in the original Super Mario Bros.