When I call The Stick of Truth a “South-Park-themed RPG”, I mean that it’s an RPG at its core and a South Park property on its surface. If you replaced the graphics, dialogue, and flavor text with something more like standard fantasy RPG material, you’d have a game that plays the same, but it wouldn’t be at all recognizable as South Park.
You might be tempted to say that this is simply how licenses of this sort work, that they’re always just veneers on top of an established genre. But it isn’t necessarily so. Consider how the gameplay of Wing Commander was clearly and obviously inspired by Star Wars, despite having a story and setting that drew more from the Man-Kzin Wars stories. The resemblance to Star Wars exists only at the level of gameplay, but was strong enough to draw comment at the time. And that kind of gameplay-level connection to the source material is what The Stick of Truth pointedly lacks.
Nonetheless, there are a few ways that the source material touches the game at a deeper level. The first comes at when you choose a character class, which, due to the LARP-within-a-game plot, is something that happens in-story, the choice presented by the character of Cartman. You have a choice of four classes: Fighter, Mage, Thief, and Jew. This both continues the Jewish jokes from the show and enables more of them in the game, but it isn’t just a throwaway gag: Jew is a fully fleshed-out character class, with its own special abilities based on more Jewish jokes. Naturally, this is the class I chose, on the basis that it’s the only one unique to this game. Then I thought: wait, it’s probably just Cleric under a different name, isn’t it? But it isn’t. I don’t really have a handle on what the specialization of the Jew is supposed to be — possibly it’s the generalist class, like Final Fantasy‘s Red Mage. It does seem to have some focus on abilities that become stronger as you sustain damage, which I suppose could be another tasteless Jewish joke, an encouragement to get your Jew beat up a lot.
If there’s no Cleric class, where do you get your healing? Largely from snack foods, but also from Butters. Butters is a supporting character from the show who I was unfamiliar with. In the game, he’s a Paladin who joins your party and can heal you with a laying on of hands, which he interprets as patting you on the back and saying “I got your back, bro” or similar sentiments. Again, skin-deep theming. Apparently the Paladin role suits the character’s innocence, but it’s just a mapping of an existing character to an independently-existing role. Eventually, however, you acquire other party members you can swap him with, and the first one you unlock is Kenny. If you know anything at all about South Park, you probably know that Kenny dies in every single episode, only to come back without explanation in the next. This inspires one of his powers in the game. If he falls in combat, rats drag his carcass away. A few rounds later, he just walks back in and resumes fighting as if nothing happened. So, here, we have gameplay drawn from the source material.
Then there’s the fart jokes. This game makes farts into one of your fundamental skills, both in combat and in solving environmental puzzles that allow you to bypass fights. This defies easy classification as deep or shallow theming. On the one hand, Cartman, who teaches you the secret of power-farting, refers to it as a “dragon shout”, specifically pointing out its resemblance to the Dragon Shout abilities in Skyrim. On the other hand, the game does use the ability in particularly South-Park-fart-joke ways, like letting you fart through open flames to create explosions.