One pixel games are a little pet experiment of mine in which I try to find “gameness” or ludicity in minimal systems, namely “pixels” – squares whose only function is to display color. You can check out other instances of these pixels here.
Following up from the simple alphabetical proximity, I’ve decided to try another method for key search, this time based upon the physical arrangement of your keyboard keys. Proximity is now dependent upon whether a key is physically adjacent to another key. Of course, the limit of this approach is that it’s limited by the many different models of keyboards. For the sake of simplicity, I’ve limited myself to the standard qwerty and azerty key arrangements
My hypothesis is that linking the virtual system (the pixel) to a physical representation (your keyboard) makes it a lot easier. The alphabetical proximity referenced an abstract arrangement of values, whereas the physical proximity is direct and obvious. The difficulty in the alphabetical prototypes came from your knowledge of the alphabet, and now it rests solely on your spatial perception skills, which are innate.
A similar mechanism is used in most current music games: the on-screen representation matches the physical arrangement of the buttons you need to press, instead of resting on an abstract system, like musical notation. This is the source of their accessibility and success: the immediacy of the stimuli-input system shortcuts complex brain functions, giving the player the impression they are “feeling” the music rather than “reading” it.