Reverse Cup was a scrapped mode from Mario Kart: Double Dash!!. It was supposed to have gameplay similar to Mario Kart 64's Extra Mode. The game's data contains fully-modeled trophies for Reverse Cup along with a logo. However, the mode never made it into the final release of the game.
Because of the cup's name, it is speculated that Reverse Cup would have the player racing on backwards tracks. This differentiates it from Mirror Mode, as Mirror Mode inverts the tracks horizontally.