The brothers travel back in time to retrieve Princess Peach, only to come face to face with baby versions of themselves, the princess and Bowser. Teaming up with their young selves will soon send Mario and Luigi on a quest of lunatic proportions as players must control both the adult AND baby versions of the Mushroom Kingdom heroes. Players use the top screen to study the land, keep track of the pair of brothers not under their control or maximize combo moves in battle.