Downer Ending: Cartman ends up killing Polly Prissypants after it turns out he killed his dolls through her while Stan, Kyle, Token and Kenny look on in horror and the 99% rally fails to achieve anything beyond devolving into class warfare.
Growing Up Sucks: After being made fun of for playing with dolls and being told to grow up, Cartman "kills" his toys.
Killed Off for Real: Clyde Frog, Peter Panda, Muscleman Marc, Rumpertumskin and Polly Prissypants
Shoot the Dog: Cartman shoots Polly Prissypants in "her" request.
Cartman finding Muscleman Marc boiling in a pot resembles the "bunny boiler" scene from Fatal Attraction.
The entirety of the murder plot concerning Cartman's toys seems, surprisingly enough, based off Umineko no Naku Koro ni.
Take That: South Park proceeds to tear up both sides of the 99%/1% rally. Making the 1% personified as one who deserves it (Cartman) and making the 99% Well meaning but poorly executed protesters that forgot what they were protesting about.