Mario first encounters Mecha Bowser in Super Mario Sunshine, during episode 1 of Pinna Park: "Mecha Bowser Appears!". After Mario finds Shadow Mario standing over a pool of water in the amusement park, the pool falls away and Mecha Bowser rises up from a pit in the ground to begin terrorising the park. To fight it off, Mario must board a roller coaster and attack it by shooting water rockets at its head. Mecha Bowser is capable of shooting Bullet Bills after Mario's roller-coaster, which can destroy by spraying them with water, and when he nears Mecha Bowser's head, Mecha Bowser will attempt to breathe fire at him. These flames can also be doused by using FLUDD. After Mario has successfully hit him with three water rockets he will break down and Shadow Mario will emerge from within.
After Super Mario Sunshine Mecha Bowser went on to cameo in a number of other Mario games, including those in the Mario Party and Mario Golf franchises.