First stage: Design
The game will be about a monochrome world with a line separating two contrasting areas, one initially white, one initially black. As you traverse you can flip yourself to the opposite area where gravity is reversed and vice versa, what you cant control is the backgrounds, which shift colors and make drastic changes to the environment, black objects are invisible in black and therefore non-interactable. White is interact-able in a black background, however and vice versa. The backgrounds change only when you press certain buttons which could flip both the top and the bottom, only the top, or only the bottom.
Now we need to get coding!