In the world of The Walking Dead monsters shamble around almost every corner. But while flesh-hungry walkers are an ever-present danger for Rick Grimes, Daryl Dixon and the rest of the crew, they definitely aren’t always the scariest threat out there. Over the past five and a half seasons of the series, the apocalypse’s survivors have come face-to-face with bone-chilling bad guys—living bad guys—that put regular old zombies to shame. Before AMC’s hit show returns on Feb. 14 and introduces new evildoers, let’s revisit the villains who have already made their mark.

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Write to Megan McCluskey at megan.mccluskey@time.com.

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