Really good game. Here's a few tips that i came up with while playing
Put MJ first and while all the people stop moving, place your other specials in places you think they'll be mostly used
Don't use bombs so much, they do help, but there temporarily, upgrades are permanent
upgrade your infection chance a lot, more zombies=better chance to kill everybody
get the magnet as fast as possible, it help collecting the extra cash so you can buy more useful stuff
zombify the guys that shoot (except hero's and FBI), less shooters=more zombies
try an infect the sides, that's where they come from and you'll keep killing them once do come
if you see a hero you haven't killed, put special over them to kill them fast and distract him while the others kill the rest
Hope this helps out, and again, really good game
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