did the series face any criticism?
Yes
South Park
The show's frequent depiction of taboo subject matter, general toilet humor, accessibility to younger viewers, disregard for conservative sensibilities, negative depiction of liberal causes, and portrayal of religion for comic effect have generated controversy and debate over the course of its run. 

when does kenny come back after season 5 Season six finale "Red Sleigh Down" who is he? Main character in "South Park" what is his role? Kenny is a student who commonly has extraordinary experiences not typical of conventional small-town life of South Park, where he lives with his poverty-stricken family. when was the series initially aired? August 13, 1997 who directed it? Brian Graden who are the chatacter? Stan Marsh, Kyle Broflovski, Eric Cartman, and Kenny McCormick what are the themes in the series? Carnivalesque and absurdist techniques, numerous running gags, violence, sexual content, offhand pop-cultural references, and satirical portrayal of celebrities. what are the other works of the director? UNANSWERABLE who plays the role of kenny? Parker and Stone voice most of the male "South Park" characters.
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South Park [SEP] Criticism
Parents Television Council founder L. Brent Bozell III and Action for Children's Television founder Peggy Charren have both condemned the show, with the latter claiming it is "dangerous to the democracy". Several other activist groups have protested the show's parodies of Christianity and portrayal of Jesus Christ. Stone has stated that parents who disapprove of "South Park" for its portrayal of how kids behave are upset because they "have an idyllic vision of what kids are like", adding "[kids] don't have any kind of social tact or etiquette, they're just complete little raging bastards".