To launch a Drone Strike, you must first unlock the Drone Strike command by securing two Drone Trails Zones (Screenshot) and making them outposts. After the Drone Strike command is available, notice that you will get a smoke grenade each time an attack is ordered. To actually order the drone to attack you must launch that grenade at the location to be attacked. Order between four to six attacks and save the grenades. Deposit the grenade in your base while the Drong Strike command is on cooldown. If you order another Drone Strike with the grenade in your backpack it will not work. When you have between four and six grenades saved, go to danger zone in the northwest (Screenshot). There will always be about twenty zombies roaming around. Drop Drone Strikes into the danger zone, then step out and back in to respawn the zombies. Repeat the process to build your total.