Andy had no idea how Rocky had managed to hide Thunderhawk City within the war zone, but he was certain that he could defend against any attack from Thunderhawk City. After all, he commanded a huge force, one that was many times mightier than Thunderhawk City's!
As a member of the Mairente family, Andy naturally knew Rocky very well. He even admired Rocky's skills and if he were to set aside his family's influence, he would give Rocky a thumbs up. Although Andy was also a City Lord of a small Sky City, he admitted that he could not develop his city to the level Rocky had achieved in Thunderhawk City, nor could he stir up as much trouble as Rocky did.
In fact, when Andy discovered Thunderhawk City, a quick connection of events made him realize who the mastermind behind those vicious attacks half a month ago was—it was undoubtedly Rocky.