besides the things others have mentioned I would have a zombie counter so you know how many are left on the map. makes it easier when firing from a tactical position and you don't have to run out to check to make sure theres not another wave coming.
is anyone else getting attacked by things that are stuck in the floors? im thinking bug of some sort. happened map 3 and maybe 4 if i remember correctly to me
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 "Symbiosis"){kind=icon}
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