Zoop is a puzzle game which challenges you to hold off wave after wave of colorful shapes that advance toward you. These shapes appear at the edges of the screen and advance towards the center. If you allow the shapes to reach the center of the screen, you lose.
You control a small triangular ship that may only be moved around the center portion of the screen. Your ship may fire at the colored shapes approaching from the edges of the screen. If you fire at a shape that is the same color as your ship, the shape is destroyed. If you fire at a shape that is a different color than your ship, your ship exchanges colors with that shape. You can destroy several shapes at once by grabbing special powerups that randomly appear.
You are allowed to select the starting stage and difficulty level. High scores are stored in the cart's memory.