In a gaming machine, a display displays at least part of a map including a plurality of cell forming courses on which a character for a player moves in a predetermined game. A controller executes each round of the predetermined game, and determines whether to trigger a mysterious bonus game with a triggering probability in each round. The controller moves the character to a destination cell in each round, and performs an event set to the destination cell. The controller awards a payout to the player according a result of the performed event, and executes the mysterious bonus game on the display in a round in which the mysterious bonus game is determined to be triggered. The triggering probability is determined by information including a position of a cell at which the character is located in each round.