Chainthesia
Try to clear all the blocks off the screen with your gun in this game. When you start, look for the small green cannon at the bottom of the screen. That is what you are controlling. To move where it is aiming, just move your mouse around it. You will see the nozzle move to wherever you are moving the mouse. To shoot, click and hold down your mouse. Two lines will show up above the cannon. The longer the lines are, the more strength will be in your shot. You get bonuses for clearing the entire screen, as well as clearing more than one block in one shot.