Super Mario Bros. Wonder is a side-scrolling platform game and the first 2D Super Mario entry since New Super Mario Bros. U (2012). Players choose from twelve characters and traverse levels across the Flower Kingdom, a new setting for the series. The game's central mechanic is the Wonder Flower, which dramatically alters levels in unpredictable ways when touched. New power-ups include an elephant transformation, a bubble flower, and a drill hat, while an equippable badge system allows players to customize their abilities. The game supports local multiplayer for up to four active players and includes an asynchronous online mode.