Tiny Troopers

This achievement requires that you kill at least three enemies with a single air strike. Air strikes are one of the three heavy weapons in the game. To obtain an airstrike, you must enter the command center and purchase them for 24,000 CP. Once purchased, you can drag airstrikes onto the screen to call them. There is a few-second delay before they arrive, so plan ahead where the enemies might move. Wait for later missions in the campaign that have more enemies to make this a breeze. Early on, you will be hard pressed to find a cluster of three enemies. If three or more are killed in one airstrike, the achievement will pop.