In "UFO Puzzle Attack!" you must defeat the invaders that are trying to conquer the Earth. Shoot them bullets of the same color to destroy their spaceships, but you must be careful: if a spaceship receives the impact of a bullet with a different color, instead of being destroyed, it will change its color!

Whenever to get to destroy an enemy spaceship, all nearby spaceships with the same color will be destroyed too. So you must try to destroy as many spaceships as you can with only one bullet to get more points.