It's likely about a cartel named 'the frogs' (literal translation). Since it's based on a true story, it might involve real - life events related to a criminal organization, such as their operations, the people involved, and the impact on society.
It could be a reference to 'The King of Science Fiction'. Maybe it's the name of a science - fiction related entity like a magazine, a book series, or a character in a science - fiction story.
In most cases, 'El Rey' is not based on actual events. It's more of a fictional narrative crafted for entertainment purposes. The plot and characters might be inspired by various elements but not by real-life happenings.
I'm not entirely sure about specific facts without more research, but it could be that the cartel had some very unique ways of operating. Maybe they had a particular code or system within the group that was different from other cartels.