12. Riot Gear Walker(s)
This guy (or these guys) appear in the season three opening episode "Seed". When the surviving group find the prison that they would make their fortress, they are confronted by a group of undead prison guards, with this particular guy coming to the forefront. There's something quite eerie about seeing the undead still wearing the outfits that they were wearing to work on the day of their demise and this hits home hard in this instance. The scene is memorable for a number of reasons - but mostly for the fact that Rick inadvertently tears this guy's face off and the scene shows just how much of an organised Walker-killing unit the surviving group have become since the events of the previous season.