If you cant beat the hard achievement, here's some help
1. Use ur points to heal your baracade to about 85% Don't waste your points pass that because u usually don't need it full health
2. spend almost all of your points on finding guns- so you keep getting better ones so you can do more head shots per game.
3. You really only need 2-3 survivors, so once u have 2-3 survivors then use your points on finding guns.
4.KEEP GETTING HEAD SHOTS, Achievment complete
Instead of the chainsaw glitch thers a better one, use the AK47 and after a few clips switch to the hunting rifle, and you will have an automatic hunting rifle, that way you can still shoot them far away instead of them coming up to you with the chainsaw, WOO 500 head shots
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 "The Last Stand"){kind=icon}