City Siege 4: Alien Siege is the fourth installment of the popular, fun-addicting shooting game. You are on a mission on a far away planet. Take your awesome laser gun and build upgradeable troops in order to battle all enemy alien units and rescue the last human survivors.

City Siege 4: Alien Siege is the fourth installment of the popular, fun-addicting shooting game. You are on a mission on a far away planet. Take your awesome laser gun and build upgradeable troops in order to battle all enemy alien units and rescue the last human survivors.