Middle the "play" again from the menu and click "play" e-click on the next difficulty selection screen. After selecting the desired game will start trouble. Your goal during the time shown above standing in the middle of the tower from attacking soldiers and shoot to destroy the tower is to protect you. You play the game with mouse, right click on the enemy when you attack you'll fire. The lower right shows you the energy, 10 energy is added when you pass each section. Also how many enemies you kill, the more money you earn. And with this money you can buy more powerful weapons are among sections. Shown in the upper right "Q" or click on the graphic quality of the game set, click on the speaker icon in the music caught me, again, click on the sound effects grab me.