Sozin's Comet is a celestial event that occurs every 100 years in the world of Avatar: The Last Airbender. It is named after Fire Lord Sozin, who used the comet's power to enhance the abilities of Firebenders, allowing them to unleash devastating fire attacks. The arrival of Sozin's Comet marks a significant turning point in the series, as it poses a threat to the balance of the four nations: Water, Earth, Fire, and Air. The comet's energy amplifies firebending, making it a crucial element in the conflict between the Fire Nation and the other nations.