just some suggestions: if the police gets into a house, there could be a percentage of getting new weapons like a shotgun? and objectives for survival? like clean the church or something? shop wouldnt be good, but maybe controlling a swat group? and a day/night cycle with flashlight effects?
what about the nearer you come the easier to shoot? because i often see killing zombies with one shot on long distance and it takes about 10 shots for shorter distances?
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