Cut all and everything into pieces and defend your tower. When pause, you can buy and upgrade. The tower stands in the middle of the map and hordes of enemies approach from both sides. Begin with small gun, but soon you can use shotgun or grenades or rocket-launcher as anti-air weapons. Don't forget to buy ammo in the shop or repair the tower.
Cut all and everything into pieces and defend your tower. When pause, you can buy and upgrade. The tower stands in the middle of the map and hordes of enemies approach from both sides. Begin with small gun, but soon you can use shotgun or grenades or rocket-launcher as anti-air weapons. Don't forget to buy ammo in the shop or repair the tower.