To unlock Dead Ops Arcade 2 you have to finish Mission 2, after the Mission the Safehouse is available. In the Mainmenu of Black Ops 3 go to Campaign, go to Safehouse and after you are in the Safehouse go to the Data Vault. Here you select in the top left corner the hidden button behind the Data Vault Symbol. After the Dead Ops Arcade 2 Intro you will earn the Achievement / Trophy. If you wanna follow my other social media...then just click awayyyy!!!! https://twitter.com/rawdanger001

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