If your arrow keys do not work, it is because you are in Google Chrome. You'll find there is an annoyingly high amount of games that do no respond to arrow keys or WASD when you're in that browser.
Try to recruit as many people as possible. After several frustrating losses with 30 people, I found out that winning is really easy if you can get up to 50~60 people.
dont buy desert eagle or shotgun
use pistol and buy assistant asap then upgrade pistol until u can buy tek then get that upgrade and do whatthen buy m4 and your good for awhile [then tap minigun].
hmm 1 wave away from getting the hard badge and of course i get the little critter to absolutely no health but i still die. i just love restarting 70 waves.
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 "Music Catch 2"){kind=icon}
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 "Dodge"){kind=icon}
 "Dark Cut"){kind=icon}
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