Press the up/down arrows to "fly". Press the left/right arrows to move. ' I know, very fun gameplay isn't it?
In 1984, Nintendo drew and wrote down ideas for a game in which Mario, a plumber in red overalls, would fly on a cloud and ride a dinosaur to shoot green and red turtles in sky-themed, and ground-themed scrolling stages. This was the first prototype they made to test the game's controls.