Great Sage

He is the leader of the Five Fire Sages and a powerful Firebender. He has turned his back on the Avatar and is now only loyal to the Fire Lord. When Aang, Katara, and Sokka arrived at the Crescent Island, the Great Sage along with the other fire sages attacked the group, until they escaped for the moment. When Avatar Roku burned the entire temple down, Zhao held him and the sages prisoner. The Great Sage argued that it was not fair to hold them all prisoner as Shyu was the only one that helped the Avatar, but Zhao didn't care and brought them all back to the Fire Nation any way. It is unknown what happened to him afterwards, but it's possible he was either imprisoned, banished, or executed for his supposed crime.