The models of the characters are from Super Smash Bros. Melee, and Mario and Luigi are seen in this trailer of a very early build of the game, driving separately, each in a simple, blue kart. It was originally called Mario Kart for Nintendo GameCube, and it is likely that this early build of Mario Kart: Double Dash!! was overhauled for the final game, as it resembles nothing like it.
The original title for Mario Kart: Double Dash. (E3 2001)
Mario and Luigi in a very early Mario Kart: Double Dash. (E3 2001)
Several screenshots released during the development of the actual Double Dash!! build shows different textures, tracks, speedometer HUD, and racer mugshots.
Early Luigi Circuit. The later version has different textures, and also note that the incorrect race placement.
Early Luigi Circuit.
Early Dry Dry Desert. The hot air balloons were removed in the retail version.
Early Mushroom City. The final revision has only one Wiggler Wagon in the course. Also note that Bowser is a partner with Mario and another is with Bowser Jr., as seen on the left of the screen.
Pressing at the end of a trial mode race (where save ghost and replay are) will bring up a series of numbers and letters, a code that stores the race time, lap time, characters used, kart used and course I.D. This was used for a Japanese contest.[1]
Some unused data has exists in a Double Dash!! demo from Interactive Multi-Game Demo Disc Version 13.
An icon and trophies for a Reverse Cup have been found, which possibly could mean that a cup where the racers drive the tracks backwards was planned.[2] In addition, early character icons have been found featuring Donkey Kong Jr. instead of Diddy Kong.[3] A button with the text "best rap time" can be found in the demo's code.[4]
The swimming Nossie from the Dino Dino Jungle track has textures for four color variants. Only the yellow and red textures are used, possibly because the first two are not as visually distinct enough from the blue, four-legged Nossie.
The icon for the Reverse Cup
The model for the reverse cup trophy
The early character icons, depicting Donkey Kong Jr. rather than Diddy Kong
Hidden in the European Demo Disc 10 demo is an early version of Sherbet Land. The name of the course is Dekoboko. Inside the objects folder includes a Wiggler Wagon, a Mario tree, an early version of Freezie, and a sign.