The main goal is to shoot as many gray squares as possible using the black square. The black square rotates around itself and shoots periodically from it's sides. In order to kill enemy squares you must put your square near them so they will get hit by your bullets. If an enemy square touches you, you lose a bit of your energy, which is shown in a thin black line below your score at the top of the screen. Once you lose all your energy, the game ends.
Every now and then, powerups will appear on the screen. These will stay on screen for around four seconds and if you pick them up, your bullers will become stronger, your square will shoot more of them or both. Also, there is a rare powerup which will make you a fast spinning red cube. While you have this powerup, you can kill enemy squares just by touching them.
By Kostas Bad Sector Michalopoulos