<P> Hudson observed tribalism as a trope in "Killer Within", which he ascribed to the reluctance of Maggie, Rick, and others in the group to allow Oscar and Axel into their clan . The Los Angeles Times journalist noted that these characters had been severed from the cultural and social fabric of their past civilization for so long that they have reverted to "traveling in a small, tightly knit group, hunting and gathering, and regarding anyone who isn't part of their it as a deadly threat ." </P> <P> The episode's initial broadcast attracted 9.27 million viewers, significantly down from the previous episode, which amassed 10.51 million viewers . "Killer Within" acquired a 4.9 rating in the 18 - 49 demographic . Despite steep decreases in weekly ratings, the episode was the night's top cable program in terms of ratings, beating out Real Housewives of Atlanta and Breaking Amish by a considerable margin . In the United Kingdom, "Killer Within" garnered 893,000 viewers, the most - viewed television program of the week on FX . </P> <P> "Killer Within" was lauded by television commentators . The Washington Post entertainment journalist Jen Chaney said that "Killer Within" offered the "most emotionally upsetting development" in the series to date, a sentiment echoed by Time's Nate Rawlings, who argued that the episode was The Walking Dead's most powerful installment since "Beside the Dying Fire". Bex Schwartz wrote in her review for Rolling Stone magazine that "Killer Within" was the program's best episode to date . The Huffington Post's Maureen Ryan described it as a "taut, terrifically paced hour" with an "incredibly powerful ending", while Eric Goldman of IGN called it "an incredibly tense (and) unrelenting" episode in his 9.5 out of 10 review . </P> <P> The fates of Lori and T - Dog garnered favorable reviews from television commentators . According to HitFix writer Alan Sepinwall, the moment when Lori and Carl share their goodbyes was the most heartbreaking event since the ending of the second season episode "Pretty Much Dead Already". Los Angeles Times columnist Laura Hudson felt it was a grim departure for a character who endured long bouts of grief for reasons beyond her control . Erik Kain from Forbes magazine found Lori's death especially difficult to watch, and was shocked by T - Dog's "sudden" death despite the fact that he "was never as prominent a figure" on the program . "As hard as these deaths were to watch," Kain wrote, "they also give me faith in the show ." Even though he stated that T - Dog died "a hero's death", Michael Rapoport of The Wall Street Journal concluded that Lori's "gut - churning" demise was the more memorable . </P>

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