Here is a State of Decay "Double Dead' Achievement Guide . To get this achievement simply play as a character with the powerhouse trait, such as Marcus, and level it up to level 6 or above, then open up the journal, go left to the personal trait page and all the way down to the defensive skills. Choose Double kill or you won't be able to do the achievement as you can only choose one skill. Now approach two zombies right next to each other and hold LB+B and you should smash the two zombies heads together and not a moment later the achievement should pop. Guide submitted by GruntShieldInc.
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