360 Canon

Feel free to keep the defense, firing from enemies that each level will be all the stronger. First, you will be attacked only soldiers with machine guns, then they will catch up with the same gun as you, but mobile. And from then on will be used planes and helicopters, and ships, and submarines. The most powerful red laser and is worth more than all. But it can be used to shoot down an enemy with one beam, in contrast to the single cores.