The object of Zoop is to eliminate a random sequence of colored shapes advancing toward you from the four sides of a square-shaped grid. You control a shape-shooting triangle trapped in the Center Square of this grid. You can maneuver the triangle up, down, right and left.If you shoot a shape that's the same color as you, it will disappear from the screen. If you shoot a shape of a different color, you will switch colors with that shape and the shape will remain on the grid. When you have cleared enough shapes from the play field, you'll advance to the next level, and the action will get faster and more crowded.
In each of the 99 levels of this game, power-ups randomly appear on the grid. These power-ups, which consist of Proximity Bombs, Color Bombs, Bonus Springs and Line Bombs, will help you clear several shapes from the grid at once. ~ Brett Alan Weiss, All Game Guide