Grass-mud horses and river crabs

The Chinese sense of humor is pretty interesting. Other than lots of potty jokes just like in English, another common source of humor are puns and jokes that use homophones (two words that sound the same but are written differently); they only work in Chinese and are hard for Chinese beginners like me to follow. These kinds of jokes are often performed by two people doing "cross-talk" where one uses plays on words and homophones to say funny or offensive things and the other person plays dumb and makes a fool of himself by interpreting everything literally.

Someone pulled off a similar cross-talk joke on the internet through a video about "grass-mud horses." This time the person who's being duped is the government internet censor(s).

When I sounded out the words "grass" and "mud" ("cao ni") I figured out it's the same pronunciation as the words "f•ck" and "you." I had a good laugh and was pleased that I understood the joke. Why the vulgar name for a fictional animal in a Chinese web cartoon? It appears that someone simply wanted to make a point about the absurdity of censoring dirty or controversial topics and tell a story with some subliminal messages.

The grass-mud horses' habitat is invaded by pestilent river crabs. River and crab ("he" and "xie") sounds the same as the word for harmony "hexie," which is a dig at the governments goal of creating a "harmonious society" which entails scrubbing the internet clean.