Double Deck is a battle course in Mario Kart 64.
The racers begin the battle on the ground floor and then can go up or down slopes to the upper or lower decks. The lower deck is colored green, while the upper deck is red. All have a wide rectangular path. At the top, there is a large square gap, which allows the racers to fall back down to the ground floor.
Instruction Manual Description
"Square" shape floors four levels high are connected with ramps allowing you to go back and forth. Because the total area of the floor is wide, you might have lots of trouble trying to find your opponents.
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