I know the goal is to survive, but there needs to be levels... unlocking/indroducing/unveiling turrets over time... otherwise.... it gets boring.... or acheivements... something! good game though!
I flew through the first couple levels... and I'm stumped at 11. Some times I don't think out side the box, or line, as it were... or is it "as it is?"
wait, where am I?
I got to union city, killed 900+ zombies, had 5 survivors at once..... and didn't win the challenge or any other badges (got the first badge in an earlier game)
every 5 levels you should be able to get a new character card.... I'm getting kinda bored with my characters..... also you should introduce a new race when you get to level 10 or 20
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