Sin

Sin is a major antagonist in Final Fantasy X. It is a gargantuan whale-like beast which threatens the world of Spira. It was named by the people of Spira who believed the beast came into being as punishment for their ancestors relying on machina and becoming a hedonistic society. By following the teachings of Yevon, the people of Spira believe one day they will atone for their crimes and Sin will vanish.

Sin is represented by the letter Z in the Yevon script alphabet. It appears in many places in Final Fantasy X, sometimes paired with the letter A, the symbol of Yu Yevon, symbolizing the beginning and the end of things.