Defense & sniping! To eliminate all zombies, wipe out zombies in the city and build the turrets!
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Story
The zombie pandemic spread across the entire globe in a few years. Survivors suffered the slings and arrows of living on remote islands or polar zones.
Almost everyone was forced to live hand to mouth. But some people risen up against the situation after the confusing.
To wipe out zombies effectively, they developed the gun turret which automatically attacks zombies. The turrets will be built at main habitats of zombies all over the world.
Therefore the zombies in the place of installation must be wiped out and the security must be ensured at first to build the turrets.
You were assigned this mission because of your skill in shooting.