The landlord should have used the formation of laser, impact and cannon. In fact, it is easy to get high marks with machine gun array in high toxic mode. I played a random game, turned around three times in a row with a machine gun, and scored 33,000 points. The landlord has basically won the gold medal, so it should be easy to turn around. The formation map will not be cut much. Remember to put two decelerators, the machine gun does not need to be completely upgraded, and the firepower of the overlapping deceleration is enough to destroy aliens. Of course, the control tower is essential ~ it is best to fill it up in the middle and early stage ~