Shoot enemies down and advance to the next level. As the game progresses more weapons become available and you will encounter more challenging enemies.
Protect your communication tower against the enemy air strike. The earlier you take down enemy planes the more money you will get! You can buy or upgrade weapons for earned money and try to keep your tower safe as long as possible.
Mutants infected by swine flu are monsters who kill people. The president decides to isolate them to one district and you are appointed to kill them all.
