The only way to escape is to destroy them first. But it's not that easy, the city is full of traps. It's impossible to hide from zombies, they always sense where you're hiding and will soon catch up with you. You are the last survivor of an army unit designed to contain the spread of zombies from a closed city. You can't negotiate with zombies, you can't bribe or promise something in return, they will slowly but surely follow you wherever you go to destroy you. Every corner or building could.
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