Banned In Germany(for about a month): The German release had to be recalled in the last minute because they forgot that showing Swastikas and the Hitler salute is illegal in Germany and needed some time to censor them.
Canon Foreigner: Chris Donnely, a member of the Drow Elves, has yet to be a character in the show. Scrapped content from the game had him playing a much larger role, and some beta voice files suggest that he was to be involved in battle (either on the player's side or as a minor boss).
Development Hell: The game was supposed to be released in late 2012 before being delayed. Twice. Then, it was delayed again, its release date was eventually 2014. This has been almost entirely due to Parker and Stone constantly rewriting the script. The season 17 episode "Black Friday" had Cartman raging about the worthlessness of pre-orders for video games, and sarcasm around the game "coming soon."
In addition, almost all of the regular cast members return to reprise their roles.
One of Us: Either one of New Kid's parents or someone in the government must've played The Elder Scrolls V: Skyrim, considering the New Kid's actual name (or government designation) is Dovahkiin.
Release Date Change: Originally set for release on 2012, but got delayed to April 2013 considering the financial difficulties of THQ. When the publisher went bankrupt and the asset sold to Ubisoft, the release date was moved even further to December 11, 2013, then March 4, 2014. It's become so infamous that the show itself has referenced it. To paraphrase Cartman, dressed in his Stick of Truth outfit: "You know what you get when you reserve a game? A big dick in your mouth!"
At San Diego Comic-Con 2013, Trey Parker revealed that the original script for the game was approximately 850 pages long. He was urged to trim the script, though he felt that eventually some of the discarded ideas could be used in the actual show. At one point, he'd thought of incorporating the game into the next season, but figured it would be more accessible as a standalone project. Though the Black Friday / Game of Thrones trilogy in season 17 (which includes promotions for the game) was probably the result of these plans.
A Game Informer magazine cover showed an alternate, unused costume design for Kenny as a princess◊. Instead of wearing the purple Zelda-esque dress, he was to wear an orange dress and would not wear his parka underneath, allowing his face to be exposed. Due to the exposure of his face, he was also shown to be wearing makeup. This was most likely scrapped because it made him unrecognizable and too much like an actual female, due to the show's art style.
The same cover shows other characters and elements for the game that were scrapped, such as Satan.
The Woodland Critters and Crab People were to be battle bosses and summons, but were cut through production of the game.
The girls were to have a bit more of a role, with New Kid and his friends having to fight schoolyard hookers in some boss battles. A "Cheerleaders vs. Whores" fight was also visible in trailers and early gameplay footage.
Clyde was also to be another final boss (as seen in the early trailer), while the Vampire Kids, Ginger Kids, and Hippies were other types of enemies that were excluded.
There were to be more Facebook friends for New Kid to add, one of them being Kenny's former girlfriend Kelly from "Rainforest Schmainforest". Kelly alludes to being "emotionally damaged" and requests that the player be Facebook friends with her rather than make her commit to an actual relationship.
Under THQ, the game was going to have several European language dubs, using the show's respective voice cast in each language - dubbed trailers were even made. When the assets were sold to Ubisoft, the dubs were scrapped, and each country only got translated text with English voices. Ironically, Ubisoft is based in France, where dubbing is almost always favored.