After Fire LordOzai declared himself the Phoenix King and passed on his former title to Azula, the High Sage prepared to crown her when Zuko and Katara interrupted the ceremony. Despite Zuko's declaration that he would be the new Fire Lord, not Azula, the High Sage proceeded with crowning Azula. He halted when Zuko challenged his sister to an Agni Kai for the throne.
This High Sage is the second known High Sage; the first one crowned Ozai in 95 ASC.
Both this sage and the sage who crowned Zuko as Fire Lord are credited to Keone Young as "High Sage", despite their different appearances. Additionally, the other sage did not wear the distinct headgear of the High Sages, recognizable by the golden flame insignia on its top.