The term 'Superman Creator' is a reference to the German-American writer and cartoonist, Jerry Siegel, who co-created the iconic superhero character Superman with artist Joe Shuster. The crossword solution for this term is 'Nietzsche, ' which is a reference to the 19th century German philosopher Friedrich Nietzsche. Nietzsche was known for his controversial ideas about morality, religion, and the meaning of life.