Z-Rox won't throw you into a mosh pit, but it will test your visualization skills over the course of 100 devilishly simple levels. Each one will show you something 2-dimensional—a letter, a number, a shape, a symbol—and your job is simply to name it. But you only get to see a 1-dimensional slice of the picture at a time, as though it were being scanned from top to bottom by a horizontal laser. You must form a complete mental image, based on your view through that 2-pixel-tall moving window. Some answers are a single keyboard character, while others require you to type out a full word.
The first 50 levels basically keep the training wheels on. You might hit a few bumps, but you can probably get past them using the time honored techniques of Walking Away From the Game for a While, and/or Shaking Your Hands Like There's Bugs On Them. It's the second 50 levels (the "extreme" levels, sigh) that will really test your sanity. You may need a pencil and paper, and possibly some Excedrin (or X-Hedr-N, as they say on the extreme streets of Extreme Town). Nevertheless, I encourage you to clear as many levels as you can before asking for help, because the sense of accomplishment for solving this one on your own is tremendous.