Zombie Combat Modern Survive

4 years and 2 months passed since zombie virus started. It infected Europe and then rest of the world. But North America and South America left untouched. Water divided Infected World from Untouched World. North America and South America tried to rebuild destroyed Infected World... Until 3 months ago! Somehow virus got through ocean. It infected all Untouched World. Only United States survived. It survived because of strong forces. And virus got through walls of very powerful forces. Remained survivors moved to bases or islands. But the most powerful base was in Sun State. It was protected by the most powerful forces. But later people realized that virus can get through anything. So, humanity had only one chance to survive: move to another planet. But that was impossible. People tried to find cure. And people found it. But they tested it only on one zombie because base was infected at the same day people found cure. You (general) probably the only survivor left in Sun State International Biggest Base On Earth. And you are the only hope for humanity. You survived because you accidently used cure. You are the only hope because only you know how to make this cure. And only you have the cure in your pocket. You will have to survive as long as you can. Shoot at zombies, collect powerups and make a biggest score!