Like its predecessor Blockade, the object of Surround is to maneuver a square across the screen, leaving a trail behind. A player wins by forcing the other player to crash into one of the trails. Twelve game variations include options allow for speed-up, diagonal movement, wrap-around, and “erase” (the choice to not draw at a given moment). In addition, the sprites can be set to operate at a slower speed, or progressively speed up through five speeds.
Description from Wikipedia