"For instance, the boy's parents die in a car crash, the grandmother's missing thumb is mentioned with a description of how it might have been removed, an account of children being turned into various strange objects by witches is given, appearances of the witches are described, cruelty in the school is depicted, and so on."
Notice that in each place there, I added a verb, so that every clause in the list does the same thing: tells the reader something that the author or his book is doing or relating.
When you have a list of comma-separated phrases that describe a list of things - all of those phrases need to have the same grammar function. In this case all of them are passive voice present-simple independent clauses which refer to examples of the "profanity, sex, and violence".
In the case of "the recipe of the "Formula 86", you have to do more to describe it; you can't just mention it in that sentence but need to add words (and a verb!) so that it fits the same pattern.
You could also make a sentence that means nearly the same thing with noun-phrase forms, also:
"Some examples of this are the boy's parents dying in a car crash, the mention of the grandmother's missing thumb and the description of how it might have been removed, the account of children being turned into various strange objects by witches, the appearances of the witches, the cruelty in the school, and so on."
What you can't do is mix the two in a single comma-separated list. Pick one, and stick with it the whole way.