Click or tap where you want the blast. Your counter-missile launches from the nearest silo, flies to that point and explodes, and anything caught in the fireball is destroyed. The blast takes a moment to bloom, so lead your shots. Each silo holds ten rounds and reloads between waves. Every wave sends more missiles, faster, and from wave three they split in two on the way down. You bank a bonus for rounds left over and cities still standing. When the last city falls the raid is over.