Supreme Mutant is the title for the office of the leader of Mutant society established in the sewers of New New York. The office is secured by a popular vote every four years. It is possible that the Supreme Mutant is similar to the "mayor of the mutants". One of the jobs as a supreme mutant could be acting as a judge in legal disputes.
Known Supreme Mutants
Raoul Inglis: This time, I'm calling for the death penalty, and not just because I'm running for re-election as Supreme Mutant!
Mutants: Four more years! Four more years!
- Only included the mentions of the title